Here, I'll show you:

But the second you stick me and one of those eight-legged atrocities into the same enclosed space, I go ape.
True story - last night, Ricky and I were parking at the Toys R' Us near my house, and as I was getting ready to take off my seat-belt, I happened to look up and see something black on the roof of the car near Ricky's seat... something black and crawly... with eight legs.
Reader, I could not get out of that car fast enough. In my haste, I got tangled in the seat-belt, tangled in my purse, but I did not let these obstacles hinder me. No, sirree, I was going to get out of that car even if it meant losing a limb, such was my terror. In fact, the contents of my purse wound up scattered on the parking lot and had to be re-collected. All the residents of Hialeah, my hometown, no doubt think I am a crazy woman. No matter. At least I was safe from the spider.
I made Ricky take it out of the car, professing that no way in heck would I get back in said car if that creature remained within. Well, he wound up killing the spider, not because he wanted to, but because the thing was so damn fast he wound up crushing it. Yes, it made me a little sad, but I must confess - I felt relieved, too.
So that's my phobia. What's yours?