I kind of - sort of - really want to run a Ragnar Relay (
http://www.ragnarrelay.com) or another similar contest. They are all 200 miles split between 12 (or fewer) people, so you run the equivalent of just over two 10ks over the course of 24 hours, and cost about $100 per person depending on how far in advance you register. There's an option to fundraise for charity, but either way part of your fee goes to the race charity.
It sounds like it would be a great training goal and an absolute blast. I'm thinking of doing the DC Ragnar Relay, and would love to make a team of 3FC-ers and friends on the US eastern seaboard! This is a super random request, but I figure none of my college friends who also enjoy running will be nearby next year anyway, and training/running with people I know over the internet would be just as fun