I have a pretty decent variety of interests, but I think it can be summed up pretty simply:
I like to "er" things. Can I make it faster? Stronger? Better? If so, then I probably can enjoy it. This primarily shows in my love affair with computers and cars, but I like to think that I'm a pretty open-ended individual. Besting my past self is pretty important to me, and I really like things that give me a metric by which to view my progress.
I specialize in computers, but I try to teach myself new skills to the best of my ability.