My school athletics department needed to raise money for more supplies, so what we did was start a raffle at our school giving out various prizes.
It did take a little investment to get the gifts, but in the end, it worked out very, very well. We managed to raise in the realm of 1000 dollars, and only needed to spend about 100 on the prizes.
We were sure to advertise it all over school before hand, and I believe the reason it was so successful was because of a combination of good, steady effort over time, and because it was a chance for the people participating to get something out of it, as well.
A great tip for fundraisers is to remember that it should be viewed as a marathon, not a sprint.