These websites should definitely spark some ideas...

http://www.good.is/everyone
http://www.worldchanging.com/
http://inhabitat.com/
https://twitter.com/inhabitat
http://www.fyse.org/
 https://twitter.com/FYSE
http://www.echoinggreen.org//
http://energy.gov/
http://planetforward.org/
http://zeitgeistwisconsin.com/
https://www.khanacademy.org/science/core-finance
http://www.kickstarter.com/
https://www.netimpact.org/
http://www.fi.co/