I have to have a costume by tomorrow night, too. Thinking of putting together some type of band/hardcore/trashy pop star outfit (leather jacket, band t-shirt, black shorts, fishnet stockings, and studded heels). That, or I'll apply make up and fix my hair pin-up girl style and put on a black dress. Asian pin-up girl (although you can forego the Asian part
).
That being said, I still live in the world where the Mean Girls' definition of Halloween still applies, and I'm too lazy to do anything creative or original.