I'll second the dental drill. That is one naaaaassstty sound.
Spiders creep me out, if they aren't in an observable type environment, otherwise they're interesting. Tarantulas don't bother me so much though.
I'm actually thinking of buying one just for the sake of getting over arachnaphobia. I've known people who have owned them, and they have never had any issues with that. Neat.

Midterms and finals always instill a sense of fear in me, eventhough I have yet to do poorly on such an exam.