My buddy calls his drill the "angry bee" because of the sound it makes. He was helping his dad build a deck and kept yelling "hand me the angry bee" all afternoon. It stuck and now his whole family uses the name.
Okay, "big metal praying mantis" is officially the best thing I've heard all week! That's way more fun than its real name. My own tool nickname is pretty lame, I just call my jigsaw "the shaky guy" because I can never cut a straight line with it. Definitely not as cool as a praying mantis.