... Actually, no real fears I've found so far.
E.g. I was actually attacked by a loose farm dog when I was 5, I have a few kinda smallish scars on my face to prove it. So you'd think that an attack at that young age would cause me to have a fear of dogs, but nope. In fact, they're my favourite domestic animal of them all. ^_^
I'm not saying I'm fearless, though, I'm bound to have a fear of something... I just haven't been in a situation where I've found out yet. :S
(Looking over the other answers here, the closest I can think of is the ocean. I say "closest" because I'm not afraid of it (I'll swim around in it with my friends, etc.), but I'm not a fan, either. I'll generally try to avoid it, I guess...)