Orlando Geeks + Charity = My Suggestion
At BarCamp in September there was a food drive, and I think for what it was the project was considered a success. I like the idea, and I would gladly give food to local needy families.
Another way our event could have an impact on the world is by participating in the One Laptop Per Child Project. $200 is a lot of money for one geek to give on her own, but if a group of 200-500 geeks donated $10+ each, we could buy 10 to 25 laptops.