Alright, I usually search the forums for this sort of thing, but it's been a while and the forums have changed, and the searches are showing me pages and pages of the same post and not being particularly helpful, so I decided I'd make a thread instead.
Here's the deal: I've wanted to play in a gestalt campaign for quite a while, and DMed a short one for a bit once mostly in the hope that someone else in my group would DM one for me to play in, and this is finally happening. I've had a lot of various gestalt ideas in the past, but mostly they tend around the overpowered, or involve a lot of spellcasting, which will be difficult given the rules of the campaign, which I'll get to in a moment. So what I'm looking for are some clever gestalt combinations, some interesting classes and prestige classes that cover each other in fun ways, something more than your standard "paladin/sorcerer" sorts of suggestions. Mostly I'm just looking for a starting off point, some inspiration for something I can do in gestalt that I wouldn't be able to pull off in a standard setting. And I'm purposely not mentioning the ideas I've got already because I want everyone's suggestions to be on a clean slate.
So here are the rules of the campaign:
3.45 edition (the DM doesn't like a few things about 3.5, so we use mainly 3.5, but some 3e things are allowed, so if there's something from 3e which I want to use, it can be argued for)
Starting somewhere around level 10
Very restricted availability of: +stat items, +save items, +skill items, fortified armor, items which simulate spells at-will (will be limited to like 10 uses per day or something)
Poison will be revamped to be particularly powerful against NPCs.
And, the main difference between the normal rules: there is a very complicated spellcasting system which makes spellcasting relatively distasteful to me, so I'm looking for a character who can do stuff without resorting to spells, and just uses spells as an occasional supplement. The reason the campaign is gestalt is because the DM wants everyone to take at least one half-spellcasting class (so ranger/barbarian is possible, for example), because he wants us to use his spellcasting system to some extent, but I personally don't want to make a character who relies on it, because he has also said that life would be very difficult for a pure double-caster type (like sorcerer/cleric or something).
So, any inspiration? I'm not even looking for some way to break these rules or anything, just something clever that isn't possible without gestalt, a good starting point. Thanks all.
Is psionics available? If so, then you can never go wrong with either Psion or Psycic Warrior stacked up on one side.
ToB also rocks.
Never mind all the goodness that Factotum can bring to any gestalt build.
Do you have any preferences?
I'm not sure if psionics is available, and neither is the DM. He generally doesn't like it that much, because he doesn't understand it very well, and I think also because I made one particularly powerful character in a previous campaign in our group (not one of his, someone else was DMing it) who happened to be psionic. Also psionics is sort of hard to adapt to his spellcasting system, and he hasn't figured out how to do it yet, or even if he wants to bother putting in the effort of doing so. ToB would probably be an excellent thing to use, though I generally don't like it much, I prefer my martial characters to be able to keep doing things instead of only getting to do them once an encounter (which is why I hate 4e), and I find it too similar to spellcasting for my tastes. And factotum is a good choice, maybe I'll throw in a few levels if I have an int-based character, but I'm currently playing a factotum in another campaign, so I sort of want to shy away from it.
Anyway the reason I didn't put up whether I have any preferences is because I just wanted to hear about some interesting and creative things which can be done in gestalt and can't be done in a normal setting, and then I would end up using these for inspiration to go and build my own character using my preferences and all that. Which I guess isn't really a job for the CO boards, since this board is meant for optimization rather than inspiration, but I'm mainly looking to do things that are normally not feasible to do in a regular campaign, and nobody will know that better than the CO boards.
Things to consider: The variant wizard from Unearthed Arcana that gives you fighter feats instead of scribe scroll and the normal wizard bonus feats. The stalwart sorcerer variant, which gives you +2 hit points per sorcerer level at the cost of one spell known (not an improved hit die). The cloistered cleric variant, for good skills. Arcane strike, to sacrifice spells to gain a bonus to attack and damage. Holy warrior, for bonus damage equal to the highest level of spell you can cast. Dread necromancer for (at 10th level) DR 4/bludgeoning and magic, light fortification, fear aura, and unlimited healing (with tomb-tainted soul). I'm sure there are other ways to benefit from a casting class without actually casting spells.
I would go duskblade or factotum gestalted with Focused Specialist Transmuter
I know you mentioned not liking ToB, but I can recommend Crusader/Knight. Crusaders already do well at tanking and lockdown. What does Knight bring in? More hit points, good will saves, and more battlefield control (and a few extra feats, which aren't that great but helpul anyway). They compliment each other surprisingly well.
Good Gestalt charatcers usually have two power sources running at the same time. If you're unhappy with spellcasting due to houserules, look to see what other things you can put on your other side. Psionics has been mentioned, but an Incarnum class or a Binder (Tome of Magic) can make a very good combination with a range of melee classes. Barbarian//Incarnate (Evil) and Rogue//Totemist both have a lot of damage output, while Rogue//Incarnate (Any)/Ironsoul Forgemaster is the skill monkey to end all skill monkeys, with insane UMD and item crafting without needing casting.
Binder is a lot worse with a /day cap if it applies to the /5 rounds abilities. Otherwise, check out the Binder's Handbook and go to town. I'd reccomend running a melee damage or tanking build alongside a full-BAB, large-HD class like barbarian.
I doubt the at-will spellcasting cap will apply to abilities, more to magic items. I could probably convince the DM that items crafted with class abilities shouldn't count for the cap, if that's what you're talking about. I don't really know anything about Incarnum, and even when I tried to read it, I didn't understand it at all. And I would have to teach it to everyone in our group since none of us know anything about it, so I'm probably going to pass on that one.
I do like the idea of using Tome of Battle, despite previously saying that in general I do not like it - in this case, it would be nice since it's more of a supplement instead of my character's main power source, which is the kind of thing I'm trying to do in gestalt - instead of making a super powerful synergistic character, I want to make one that can do new things that I normally wouldn't be able to do. For example, one of the ideas I had (which I didn't mention earlier to keep the ideas flowing more freeform, but I figure I might as well go ahead and mention now) was a shapeshifter-type, going full druid and/or maybe throwing in some master of many forms levels, and then building up martial classes on the other side, tossing in fighter, monk, barbarian, etc. levels, so that I am essentially your standard martial frontline type, but I can also shapeshift extremely well, and also cast a few spells to supplement all of this - a combination of abilities that would generally be impossible. This is where Tome of Battle would be interesting to me - a Tome of Battle shapeshifter would be an interesting combination of abilities. I'm not certain I would want to go 20 levels straight in a Tome of Battle class though, but I don't know how well they do at multiclassing. Are they like monk, where you need to take 20 full levels (1st level dips notwithstanding) to be worth anything? Or could I go with something like 10 swordsage levels in a 20 level build and still get something useful out of it?
Edit: Something else I should also say, I always try to build a lot of utility into my characters (I've never had a character with an Int score less than 12, almost everything I make is a skill monkey to some extent), and I'm not opposed to taking tons of classes for just a few levels at a time to get where I want to get, I've had characters with as many as 7 classes, etc. So that's one reason I'm not asking for specific builds, because I'll overanalyze my builds and toss in a few levels here and there of any number of classes, I'm just trying to get a kickstart into thinking about ideas which are unique to gestalt.
Edit 2: I kept calling Tome of Battle "Tome and Blood." Too much early 3e for me :-p
Tome of Battle is incredibly dip-friendly. All the maneuvers in Tome of Battle have an initiator level requirement, but your initiator level in a ToB class is your level in that class plus one half of your levels in all other classes. For example, two levels of swordsage at 7 and 8 can get you +2d6 sneak attack all the time, and a ranged touch attack for 5d6 typeless damage, a teleport ability, and a range of counterattacks and single-round buffs once per encounter. I'd avoid most melee strikes for a shapeshifter, as they tend to get a lot of attacks on a full attack, rather than a single big hit.
Also, look at Warshaper (CWar). It gives a lot of good stuff for anyone planning on spending a lot of time shapeshifted. Fast Healing, immunity to crits, +4 Str/Con, an extra natural weapon, and the ability to switch forms without expending another wildshape use. The capstone particularly adds a lot of utility as well as combat ability.
How about a Binder//Warlock? It is absolutely dripping with flavor, and most of the abilities it gets are at-will. It also has tons of versatility.
I haven't seen Dr.Rocktopus in a while, so I'll go ahead and do it for him ......
war weaver is always awesome for any build. 
A good combo that I usually think about when the topic of Gestalt characters comes up is a Ftr/Wiz/Bladesinger (Cwr)/Abjurant Champion (CMage).
Then you take the feat Arcane Strike and you've got the ability to do a good amount of damage and have a really good ability to hit most things with any spell levels that you don't end up using.
With this character build you'll have good spellcasting ability, which you can use to really compliment your character or the party both on and off the battlefield, really (and I mean really) good defensive capabilities with Abjurant Champion, you'll also have pretty good; HP, BAB, as well as saves, and lastly your combat ability will be practically on par with a straight fighters.
And if you wanted to you could also add a few levels into Rouge so that you could practically do everything. With it's skill selection and trapfinding ability, you can fit any role that there is to fill in the campaign.
Also, another class that wouldn't be bad to add at least 3 levels into would be Swashbuckler, especially since you like Int, if you just pump that up to at least 16 maybe 18, especially with an alright Str and really good Dex. You'll get Weapon Finesse for free, and get Insightful Strike so that you'd be able to add your Int to damage rolls.
Oh, and being an Elf ain't to bad neither.
Ok, but other than all of that you can also do a a Spellsword (Cwr) combo. Or, Arcane Trickster (DMG). A Druid/Monk combo would be really good. Rouge/Assassin/or Shadow Dancer even. Also, a Barbrian/Sor/or Wiz/Rage Mage. A Monk/Pal with a Vow of Poverty would be really devastating against evil foes and you could always focus more on a specific type of evil with either the Hunter of the Dead or Knight of the Chalice prestige classes, both from Complete Warrior. Oh, another fun combo would have to be Wiz/Warlock/Monk/Eldricth Theurge (Complete Mage)/Enlightened Fist (CAr), with this class combo you'd be the ultimate Unarmed combatant with a very good selection of magical ability that compliment your character as well as your party members.
Well, those are just some of my suggestions, I could give you more but I think that this is enough for now.
Scout/Rogue/Dervish would be fun, you get sneak attack and skirmish on top of dervish dance then you take the skill trick that lets you tumble to make someone flatfooted. Take the travel devotion feat and you can move your base speed as a swift action then make a dervish dance.
Prestige classes that are essentially class combinations-such as the arcane trickster, mystic theurge, and eldritch knight-should be prohibited if you’re using gestalt classes...
So abjurant champion, arcane trickster, bladesinger, eldricth theurge, enlightened fist, rage mage, and spellsword are all things the gestalt variant suggests the DM bans.
I would try the Druid because you don't rely on spellcasting as much as other Full-Casters do and still get to try out that new system.
As a secondary class I would choose Barbarian or Fighter to gain some combat power.
If you want to go a completely different way, check your DM if Monster classes are allowed in gestalt. If they are, just combine one with something that increases it's current abilities.
Dragon Shaman/Factotum will let you buff allies and generally rawk out without built-in reliance on spellcasting, psionics, or ToB.
And excuse the manic question spree but what would be the best feat selection for the build if I want the TWF tree and stormguard warrior?
druidic spellcasting combined with ninja stealth and skill monkey abilities, one of my personal favorite gestalt combos.
if psionics are allowed, perhaps go Barbarian/Divine Mind. picking mantles that either complement your combat abilities (travel, destruction, etc) or help cover your deficiencies (knowledge, mental tower, etc).
I'm gonna be playing a gestalt game starting at 20th and my dm allowed paragon template. so I took 20 factotum 5 iaijutsu master and have font of inspiration 8 times.... good stuff.
Other than that I'm curious whether a straight Warblade//Factotum would make a stronger character than Factotum/Swiftblade//Warblade/Eternal Blade. (Wizards should be more creative on naming classes)
I mean, why would an introvert hermit seek adventure anyway?
An introverted hermit wouldn't. However, since there's nothing that says druids have to be introverted hermits, it's a non-issue.