The simple version: FairShare lets bands earn money just by having an artist profile at ReverbNation.com.
The simple but more extended version: If you have a band profile in ReverbNation and click on a link saying "I want to activate FairShare", from that moment you'll get 50% of the ad revenue from the ads displayed on your profile. This means that how many more people you direct into your ReverbNation profile, the more money you'll earn. Just to give you an example, Merankorii's ReverbNation profile  isn't something I lead people into (like I don't do it to Merankorii's presence on MySpace or PureVolume), and I've earned $.88 regarding August. Artists can only get their FairShare 60 days after signing into this program, and if their balance scores more than $20 (against the $100 from AdSense). Revenue updates are made monthly, and as soon as you're eligible to widraw your earnings you can make the transaction with one click.
Why is this so great? Well, this could be, for instance, a great alternative for those bands in net-labels (or for net-labels themselves): not only you get free hosting and a social network that can lead more people into your music, but also you can earn money from your work. But, most importantly, this finally solves the issue about how to give artists money while fans keep getting the music for free .
 - http://www.reverbnation.com
 - http://www.reverbnation.com/merankorii
 - http://tinyurl.com/2788g5