Anything with fangs/venom/stingers that are harmful to humans (resulting directly from a chance encounter with a hornet nest when I was little, and a yellow jacket nest a bit afterwards).
Heights that are above 6 stories.
Pretty much anything related to a hospital stay, or surgery, or most anything medical in nature. I just can't stand the thought of someone/something slicing me open and poking around with a metal rod...
Yeah, strokes, heart attacks, etc..
Drowning. And for that matter, being over a deep body of water (even though I can swim).
Death in general.
The military draft.
Never actually flown so I dunno how I'd feel.
Probably a few other things that I can't remember or think of at the moment.