Home Power Magazine published an article in their June - July 2011 issue that discusses this interesting option. In those states where the laws are favorable, people in the same community can form their own LLC (Limited Liability Corporation) and build a solar array that can provide energy for sale back to the local power company. Members receive credit towards their utility bill in proportion to their investment.
One thing that is very attractive is there is no need to modify any wiring or metering in any of the members' homes. When a member decides to move and sell his or her house, the membership can be sold simultaneously. The new buyer may be able to roll that investment into the mortgage as a part of the value of the home.
You can read the entire article at Home Power Magazine's web site: http://www.mygenerationenergy.com/2011/06/home-power-magazine-community-energy-solar-gardens-a-growing-trend/