What do you do?

My roommate's birthday is this Friday, but because of a thousand different factors, and my boyfriend and I having to put every DIME we make into getting a new apartment (which, by the way, is the FAULT of said roommate... but I won't get into THAT rant) I only have about $20 to my name right now. That has to go towards vet bills this Wednesday and I'm sure I'll also be dipping into savings. I can't make her anything because I really don't know her well enough to know what she would like. I'd like to get her something though, especially since she bought me something on my birthday.

Any suggestions?