Prince of Petworth just posted a press-release for "Hill and Go Seek", which is basically a scavenger hunt on bicycles. This looks like fun, and it would be a chance to explore a part of DC I don't get to very often. I used to work on Capitol Hill, but its been years since I've been over there and I've heard that it has vastly improved. And it is all for a good cause. What can be better than having fun for a good cause?
This also happens to fall on the same day as the DC State Fair. I see a day filled with biking, contests and fun in my near future!