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

2009
The Ruins of the Unsustainable: Searching For Answers to the Suburbs
A classic Worldchanging piece by Julia Levitt, in which she ponders Bruce Sterling and the future of suburbs...

2008
Biomass Charcoal in Eastern DRC
Ethan Zuckerman looks at efforts designed to end the developing world's dependency on charcoal...

2005
Joel Makower: Clean Energy -- It's Not About the Environment
Joel Makower asks "Why aren't you buying clean energy?" given all the benefits...

Other recent "look backs":
July 29
July 30
August 2