I received an offer for a credit card with zero interest on purchases or balance transfers for the first six months, and for the first time, took the lender up on the offer. I found myself with a card having a $20,000 credit line and a blank check for a balance transfer. The fine print showed the transfer was subject to a 3% fee, but capped at $50, so I wrote a check to my brokerage account and deposited $19,950 into a money market fund earning 5%. For the effort of writing that check and making the payment back in 6 months, I’m ahead $450. I’ve read there are people that manage to find offers such as this one on a regular basis, making a few thousand dollars a year just by shifting this money around. I’d think there are only so many banks making such offers, and at some point too much available credit will impact one’s credit rating, but for now, I’ll take the $450, and be sure to make the payment in full when this becomes due.