Already doubling the number of cities involved in 2008, EarthHour.org is expecting even more cities to join their action on climate change.
The global initiative, supported by WWF, began in Sydney turning their lights off, and has grown to reach over one billion people all over the world. In 2009, at 8.30pm on March 28, you can also turn the lights off for one hour – the Earth Hour.

http://www.earthhour.org/