ANAL GAPING! Mostly really, really, impossibly large toys, fisting, hand balling. Things of that nature. I mean anal is great, but seeing someone stretch their ass to the limit and stretching my ass to the limit is my "fetish." I love to see folks who have stretched and fucked their asshole to the point where it has swollen red and purple lips. I want to feel my asshole swell and squeeze my "lips" between my fingers. Haven't quite got there, yet... still trying
Other than that, cum and pre cum eating/drinking. I don't know where the line gets drawn for where it becomes a "fetish" or not.