You know those machines that count your piles of loose change and spit out a voucher you can convert into cash? At least around here, most supermarkets have the machines, but I've never used one, since they charge nearly 10 percent for the coin counting service.

Until, that is, I walked by a Coinstar machine at a local grocery store and noticed that it would waive the transaction fee entirely if I was willing to take my money in the form of a gift card or certificate to one of a number of major retailers, including iTunes. That's perfect, since my $46.24 might not seem like all that much were I to spend it at Amazon or one of the other included stores, but when used for songs and iPhone apps, it will provide a significant amount of entertainment. (This is, of course, not news, since the service has been around for some time, but if you pay as little attention to machines in supermarkets as I do, it may be news to you.)

Apple presumably pays Coinstar the 8.9 percent fee that Coinstar would normally deduct from such transactions. That's a small price to pay for spreading the iTunes meme even more broadly than before, and in areas that might be noticed by people who don't normally think much about Apple.

According to Coinstar's Web site, most U.S. families have about $90 in change around the house, which implies there is about $9.5 billion sitting around in jars and under couch cushions. Apple may not be in need of a federal bailout, but I'm sure the company will be happy to get its hands on some of that petty cash.

If you aren't sure where there's a Coinstar machine near you, the company's Web site offers a locator service that shows you the nearest machines in the United States, Canada, the UK, and Ireland. Not all machines offer the gift card/certificate option, so pay attention to the details when locating a nearby machine.