dineatohon.com - A meal together saves lives
I just saw a post about this on Guardians blog. It looks like a good idea, you invite people over for dinner and they donate money to this cause as payment for their dinner.
I'd probably not be able to ask anyone to pay for a dinner at mine, I'd end up donating the money myself. Still a good and worthy cause.
Have a look at their site and see if you can't get some event together.