I just got back from a winter-camping weekend with some buddies, where the greatest shock was not how many of them snore like chainsaws, but how few of them knew about AmazonMP3. Clearly I've been remiss in my Cheapskate duties!
For others unfamiliar with it, AmazonMP3 sells DRM-free MP3s for 89-99 cents apiece; most albums sell for $9.99 or less. The key phrase here is DRM-free: Songs purchased from the service (which currently boasts about 3 million tracks) have no copy protection whatsoever, meaning they'll work with any gadget that plays MP3s: iPods, Zunes, smartphones, Creative Zens, Sansa e280's, and so on. If you've ever purchased music from an online store, only to discover that it's incompatible with your player or won't play on multiple PCs, this should come as good news indeed.
Another perk: The small utility that downloads songs to your hard drive can automatically add them to your iTunes or Windows Media Player library, ready for syncing to your portable player. Easy-peasy.
To find out more about Amazon MP3, read my complete review of the service. Needless to say, I'm a huge fan, and not just because it saves me money.