Read this great article by Andy Raskin from Business 2.0 entitled 'Giving It Away (for Fun and Profit)'.
I especially like this:
How a Sharing Economy might work
1 Sharon records "Sharin' da Love" using her guitar, her PC, and a few beats she downloaded from the Internet.
2 Sharon uploads "Sharin'" and attaches a Creative Commons license that allows free downloads and noncommercial use.
3 Thousands of people download an MP3 of the song. Some send it to their friends, and Sharon's reputation starts to grow.
4 Audiophiles buy higher-quality MP3s. An ad agency licenses the song for a commercial. A producer hires her to write a new song.
5 A record label, noting the buzz, releases a "Sharin'" remix under full copyright, earning revenue for both the label and Sharon.
6 Free content expands the audience for digital music, boosting demand for computers, software, and Internet services.