I have gotten offers in the past for 0% balance transfers (for 6 months) on the Midwest Airlines credit card. You get 2,500 miles for first purchase / balance transfer and up to 5,000 additional miles for a balance transfer in the first 30 days (1 mile for each $ transferred). I think there is a balance transfer fee and a limit of $20,000 on balance transfers.

Card is offered by Jupiter Bank.

I believe Midwest Airline miles can be used on American Airlines. However, the miles cannot be combined for award travel.