that is another nice site. that and billmonk are a bit different in their goals than settleup.

settleup is meant to be a simple calculator that you can use without creating an account or logging in. if you want something to keep a history then those are good solutions, but if you just want to settle up after a trip with friends you might not want to have to create an account, and might not care about keeping a history. then you're stuck figuring it out on paper or in excel. my intent was to make settleup a little easier than excel and more convenient than other similar sites.