Listen to Your Friend's Music Library for Free

What if your media player came pre-installed with all the songs you like?

While Reble Media Player doesn't quite go that far, you and your friends probably share similar musical tastes, and Reble lets you listen to the songs stored on your friends' computers as much as you like.

This can vastly increase your music collection without any effort at all. All you need to do is to install Reble (and somehow convince your friends to install it too) and exchange usernames to begin sharing songs. It's a clever viral strategy to grow the number of users, but ultimately, the question is whether Reble is legal (they don't seem to be paying royalties).

There are a couple limitations, however. A particular song can only be streamed to one computer at a time, and you can't download it to your computer. You also need at least Java 6 installed.