The world's two worst variable names
oreillynet.com
oreillynet.com
Which is at least better than "foo".
My favorite though is still expletives as variable names. You can tell from the number of them just how frustrating the code was to write. I recall digging through some particularly hairy boot code a few years ago where /every/ variable name was a swear word. Must have given the developer fits to get working. :-)