I knew a kid in high school that dressed up as a tampon one year.
dress up as some seventies dude with platform shoes and a big afro.
Maybe you could do something political. Like dress up in a monkey suit and have a name tag that says GW. Or the other way, dress up as Kerry but add the furrowed brow and bolts of frankenstein. Or go undecided and do half monkey half frankenstein.
Another one, it would be interesting if you could rig this up. Dress up like a GW bush marionette(sp?), like in Team America. And at the controls put small representation of Cheney attach to it.
Goes as one of the YMCA guys, that's pretty offensive.
Here's a gross one. Dress up as a little kid, get one of your girl friends to play "mom". But in this case the umbilical cord is still attached. You could put all sorts of nasty stuff in the cord. Although you could actually play a baby that's being pushed around in a shopping cart.
How about some crack addict. You could have needles sticking into your arm and such.
That's all for now.