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

2009
Our Urban Future
Adam Stein shares a handful of links that take a data-driven driven look at cities, which reveal fascinating patterns...

2008
Nothing for today!

2005
Amory Lovins vs. James Kunstler
James Cascio reflects on a debate between Lovins and Kunstler published in Salon, which triggers a great conversation in the comments section on the language of pessimism versus optimism...

Other recent "look backs":
May 21
May 24
May 25