To begin with there is no real cash return(BEY or IRR) bcs if you put the money which you would have applied towards a bill into a savings account your effectively cutting off your opportunity cost (lifestyle + time = money). And if you cant find anything yielding you more than 4.6% with the formula i gave you then you have some other serious issues imho.

Secondly, your better off of looking at this as a free loan to be applied vs. your credit score.(therefore not entirely free) If you want to fool yourself into beleiving your "making" money go right ahead. Remember, that IF like many of us you pay your debt in full at the end of each term making it not subject to fees, than its truely no difference. OTH if you make the minimum payment, then this might be worth some of your money but than again you have entirely different issues.

Lastly, you can do much better than 4.6% using FDIC insured payable at will savings accounts. Almost 100 beeps better, fyi.

-Signing off, running to catch a plane...