Looking back one, two and five years ago today (give or take!) on Worldchanging:

2009
(Un)Inhabitable? - Art of Extreme Environments
Regine Debatty reviews an art exhibit that explores the meaning of living in extreme environments...

2008
The Locavolt Movement: Pushing For Energy Independence
Julia Levitt reports on a recent story on the "locavolt" movement...

2005
Apocaphilia, Peak Oil and Sustainability
A classic Worldchanging post by Jamais Cascio in which he lays out why there's still cause for hope despite the challenge peak oil presents...

Other recent "look backs":
September 10
September 13
September 14