Earth Hour: A brilliant ad campaign.

Here.

Excerpt:

Just a thought - I wonder how much WWF donated money went into the pockets of Leo Burnet?

The thought that turning your lights off for a single hour in a year will make a difference is pure silliness. Even funnier still is that you wouldn't even be bothering unless an advertising company told you to. And again, this is just trendiness. It will all be forgotten the next day.