The most groundbreaking idea in the last 2 decades-for me, is the idea of microfinance, granting small loans to poor people with no collateral. It made perfect sense, and I think one of the most innovative, creative solutions to solve the problem of poverty, help people who want to help themselves, and not just give handouts.
http://www.businessweek.com/magazine/content/05_52/b3965024.htm