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

2009
Earth Day: 10 Big, Really Hard Things We Can Do to Save the Planet
If you missed it or forgot it, this list of the top 10 big, really hard things we can do to save the planet is worth reading. While traditionally Earth Day is a day devoted to making green accessible to all - when each of us is invited to take small, individual steps toward reducing our carbon footprints, limiting our waste, or restoring the environment - Sarah and Alex say screw the little things...

2008
The Top Stories, Earth Day 2008
Worldchanging noticed that this year's coverage of Earth Day differed from past years. The focus of the articles shifted away from defining the problem (startling statistics about pollution, global climate change and environmental destruction) to helping people discover the solutions, or at very least eco-branded products and services portrayed as solutions...

2005
Going Beyond the End of the World
Alex Steffen acknowledges that worldending is easy, and perhaps even a beneficial thought process to spur survival, but ultimately also distracting. The challenge of imagining worthwhile futures receives far less attention than it ought to...

Other recent "look backs":
April 15
April 16
April 19