Yay! I've just released the first version of a shared expenses manager. It's perfect to manage shared houses budgets or weekends off with friends.

Have a look, comments and feedback are welcome.

http://blog.notmyidea.org/how-are-you-handling-your-shared-expenses.html
The app is on http://ihatemoney.notmyidea.org and the code on http://github.com/ametaireau/budget-manager/
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