Payment Web 2.0 / social network - I don't remember the website!?

I'm looking for a web 2.0 / social network I heard about that allows people to keep track of payments to your friends, roommates, etc.





I'm moving into an apartment with some other roommates and I know this online system I heard about can keep track of who owes who what, instead of trying to remember all those IOUs. It keeps track of who owes who for groceries, cable, internet, etc...





But the problem is, is that I don't remember what the website is called!





Can anyone help me? Thanks!

Payment Web 2.0 / social network - I don't remember the website!?
http://www.igroops.com/





http://www.mybillq.com/





http://www.mypaynet.com/