Armory, Library, Enchanters Tower, Alchemist's Tower, Storage, Bedroom, Kitchen, Cellar, Main hall, and something else...
Cellar can always be chosen as long as you've built a main hall I think.
So wait... I could have a main hall, an armory, a library, and a cellar. That's it? Damn that svcks.
EDIT: Nevermind, I realize main hall doesn't count for the three wings. Still wish there was more though.