Wow, after reading everyone's varied fetishes I feel kind of vanilla. Obviously I'm into diapers, and I like dressing like a little girl, but I don't really consider that a fetish. I just like to act like a brat, and that seems to be dressing the part.
As far as things that actually turn me on, well let's see. I have a panty fetish. Buying and trying on cute panties always gets me excited. A gift of panties is almost always rewarded. And even though I'm not really into girls, seeing another girl in cute panties gets mine sort of wet.
As a brat I like being spanked. I prefer to be spanked with my panties on, but bare-bottom is good too, as long as it's OTK. I like being felt up in the position too. I feel so vulnerable with my bottom in the air.
I like anal sex. Not really on the level of a fetish, but I do enjoy it from time to time. I have to be in the mood, otherwise it's just uncomfortable.
I love being taken from behind. Bent over a couch, face down on a bed with my fanny in the air, or even just a pillow under my hips. I masturbate in this position most times, while fantasizing about being fucked this way. My best orgasms have been doggy-style.
I LOVE oral sex. I give great head, and I love being licked. 69ing is the best. I've even done ATM, but only right after (or during!) a shower.
These are the things that turn me on. Thankfully they're easy to talk to new partners about, although I haven't had any new partners to broach the DL subject with.