My major one: Heights
Driving over bridges (tied into heights, since it's the bridges where I can't see ground on the side that give me sweaty palms and make my heart beat like mad. I also get this strange feeling like I have to keep myself from turning the car off the edge. I thought that was really weird, but a good friend of mine just told me his wife has the same feeling, only worse: whenever she's at a height, she has to hold herself back from throwing herself off.)
Other people holding knives (not knives in general, just bigger knives in other people's hands). Guess I just don't trust the other people (or maybe was traumatized by the psycho home-ec teacher who noticed that I stepped back when she grabbed a big knife, and 'joked' by waving it at me...great teacher, huh?)