Boo-tastic

We're getting down to the wire on Halloween and I need a costume idea for the office. Obviously, it has to be something I can work in. Ideally, it will be cheap, creative, and comfortable.
Not in the running:

• Sexy Oscar the Grouch (or any other sexied-up Sesame Street character)
• Zombies (a little over this nationwide obsession. Also, most of these just make me want to vomit.) 
• Anything that shows belly. (nobody wants to see that)
• Anything that involves technology (remember: cheap.)

Oh, what the hell, I'm cutting two holes in a sheet. Do you think it needs to be white?