I think the raffle I did at one of Rick's events worked well for a first try. I donated a geocoin to the cause, made up a jar stating the proceeds would go to the cause and people put their user names on a dollar bill and placed it in the jar. A few people put their names on larger denominations and/or entered a couple times. The $55 collected was more than 5 times the amount that the coin cost, so it was a success. I think if it was done more often and people got used to the idea it would help out quite a bit.