I saw this recently (
http://kickingitforward.org/ ) which might be a more organized way of executing what you've mentioned. I agree with the need to support the community with the hopes they might support you, but there is somewhat of a disconnect between showing you've paid it forward in previous pledges. I think what frequently happens is someone decides they want to run a crowdfunding campaign, they choose the Kickstarter platform, then they hastily back some projects prior to launching their own campaign, all so that it says "First created, 7 Backed". You risk looking a bit less-than-genuine, but I would say that it is probably better than nothing ("First created, 0 Backed")
- Tom
P.S. Definitely going to look more into
http://kickingitforward.org/, although the rolling 5% tax via Kickstarter's cut is an intriguing idea.