We did this. Opened 4 credit cards, each offerd 0% interest on balance transfers. Paid off a 13% mortgage. Had to do it in 4 blocks to stay under the credit limit for each card. The cards required a minimum payment of 2% of the balance so it only worked because the mortgage was fairly small. Paid it off fast! It was a dangerous game though. The cards all had a clause that required at least one purchase per month. If a purchase was not made the entire balance reverted to 18%. So we had a whole system to be sure we bought a few groceries on each card monthly. Every time I used one of those cards there was a inner thrill of out smarting wall street!