Looking back one, two and five years ago today on Worldchanging:

2009
Beth Kolko and Design for Digital Inclusion
Ethan Zuckerman reports on Beth Kolko and her research group Design for Digital Inclusion at the University of Washington. The group includes undergrads, grads and faculty across fields who focus on a wide variety of topics: technology in Central Asia, non-instrumental uses of technology, technology and autism, games for development, and others...

2008
Greenhouse Gases: Where Do They Come From?
Clark Williams-Derry shares a geekalicious image from the World Resources Institute that shows how human activities contribute to global warming; a must see for any Worldchanging reader!...

2005
Manifesto for Free Fruit
Regine Debatty points out a fun resource: Fallen Fruit, a grassroots project for mapping all of the "public fruit" planted on private property that overhangs public space...

Other recent "look backs":
June 18
June 21
June 22