The monthly statement for one of the Credit Cards I used for 0% balance transfer arbitrage just arrived. I somehow managed to misjudge and overpaid the amount required to clear the balance just before the 0% period ended. The amount overpaid was one minimum monthly payment - so I now a $240 credit on a CC I never use. Ah well, I'll just have to use this card to pay a couple of grocery bills at the supermarket. This will teach me to double-check the final amount required to clear a CC at the end of a 0% balance transfer period.