What is Your Cat Afraid Of?

Our cat is not afraid of much, and has decided that our big pit bull mix Willie is just a clumsy oaf beneath her notice, but she is not fond of a clanging metal sound. I notice this when I am getting out cookie sheets, or if a pan lid slides down on the stove. For some reason she finds what I think of as a benign noise to be alarming. She's also not a fan of storms and will disappear under the bed until the storm noises have passed.