We had financed a car through the dealer, which meant paying 5% interest for the duration of the loan (approx. $50/mo.).
I opened a 0% percent interest rate credit card, transfering the balance of the auto loan to it. All I had to pay was $50 for a transfer fee. I make the same payment amount as I did on my orginal car loan.
Once the 0% interest rate ends (in 12 mos.), I'll transfer the balance to another card. In the mean time, I'm saving $50 a month on interest.