Fundraising Ideas

I just got elected as the treasurer/fundraising chair of my a cappella group. The fundraising chair aspect of the position is new, and I need to come up with/organize ideas for a fundraiser for our group. We're one of six groups on campus, and the only non-audition one. A few other groups on campus have their own fundraisers like pieing a member in the face, doing Valentine's Day singing telegrams, and a fundraiser bingo. I want to find an idea that can be unique to our group that isn't costly to put up. I'd love to hear any ideas!