I'm a big fan of a program on Showtime called 'The L Word'. On this show, one of the characters maintains a giant whiteboard with a ginormous diagram of all the main characters and with whom they've all slept and so on and so forth. It's a pretty darned big chart!
I was browsing the show site and ran across this interesting little application that lets people start their OWN charts. I'm sorely tempted to start one of my own. Of course...it wouldn't have anything to do with sex. It would be a good-friends chart or a good-hasher-buddy chart. I think it would be interesting to see what kind of social dynamics are at work (particularly if hashers were used).
Again...it's just a brain-stormed idea at the moment.