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

2009
Temporary Spaces and Creative Infill
After an unexpected dining experience in which she discovered that two businesses, each with unique menus and ambiance, shared one restaurant space, Julia Levitt wondered: "why don't relationships like this form more often?" The answer leads her to explore the nature of temporary spaces...

2008
Can Our Allocation of Energy Represent Our Values?
Carey King examines society's struggle to understand the value of output of renewable energy systems and processes and asks: "for every unit of energy input from field to fuel, how much of that input should be responsible for each product?"...

2005
Further Concentration
Jamais Cascio explores Pyron Solar's new novel solar concentrator system, and thinks it might just be as good as it seems...

Other recent "look backs":
July 19
July 20
July 21