Earlier this year I posted what I thought was an excellent Christmas gift idea; take that jar of loose change you've been accumulating to the nearest Coinstar coin machine and convert your change into gift certificates. While Coinstar charges up to 8.9% for change-to-folding-money exchanges, you get full value on gift certificates for a variety of popular companies, which make excellent gifts for the holidays.

Now Coinstar and Amazon have sweetened the deal even further. Turn in at least $40 in coins, take the total in an Amazon gift certificate, and you'll receive another free $10 gift certificate (by mail, in six weeks) for your trouble. That's a 25% return on your money. Try to get that from the market.

The offer is limited to one per household, so this isn't a bonanza. Still, every penny counts, and here's a way to get 1,000 of them, free. Ka-ching!

Thanks, My Money Blog