Making their way to PayPal’s Innovate 09 Conference in San Francisco this week is an innovative UK based start-up called Expensure that helps friends, flatmates and travel companions track, manage and resolve their shared bills and expenses.

Expensure aims to make your life easier by using a unique algorithm to work out who owes who what in just a few seconds, saving you from the pain of working it all out manually. By comparing who you own money to, who owes you money, and what money these other people owe to each other, Expensure can calculate the easiest way to resolving your financial conundrum as fast as possible.

The tool should come in particularly useful for students and home sharers who are frequently looking for ways to resolve in house disputes over your typical household costs like rent, broadband, gas, food etc.

Expensure also offers a collaborative Shopping List making it quick and easy for flatmates and travelmates to check off who owes money for what.

According to an interview with IndieStartups, co-founder Andrew came up with the idea while “sitting around one day trying to work out who owed who money after about three months of bills and expenses had been accumulated. We had each paid for loads of shared stuff, and owed money for many different bills. In the middle of trying to work it all out for the tenth time we thought, why don’t we just make an app that does it all for you?”

While not the first company to target this niche, see BillMonk and Scred, the company is making headway having managed to secure a place to demo at Paypal’s SF event this week, in a bid to play a part in Paypal’s ambitions to feature a ‘payment resolution’ mechanism in it’s payment platform.

If only Expensure had only been around in my student days…me and housemate Jason would still be friends today.