For years, I have written and lectured about how your songs (as downloadable MP3s) are your very best promotional vehicle. They contain value themselves, but making the process of getting them into your fans' iPods and CD changers is where you can trade a tremendous amount of value for the personal information and the attention of your fans (that can lead you to bigger sales).
Until today, record labels have taken the hard line against free downloads, since they're in the distribution game, first and foremost. But what happens when companies like Disney and Universal, with more urgent things to sell (like movie tickets), realize that audiences are willing to trade the value of a free download for some attention?
That's the idea behind SpiralFrog, a new venture that aims to let music lovers download songs for free in exchange for reviewing some advertising. The files will probably have all kinds of crazy DRM on them, so I wouldn't expect to see a huge adoption rate at first. But it's interesting to see that someone on the label side is thinking about these things, too.