Air Force and DARPA University Nanosatellite Program

Europe (DLR): http://www.kp.dlr.de/solarsail/Welcome.html

Europe (U3P): http://www.u3p.net

U.S., Benjamin Diedrich: http://www.ugcs.caltech.edu/~diedrich/solarsails

Article in SpaceViews - by Patricia Mulligan, NOAA