Via The Guardian:
Coca-Cola has been forced to withdraw a Twitter advertising campaign after a counter-campaign by Gawker tricked it into tweeting large chunks of the introduction to Hitler’s Mein Kampf.
For the campaign, which was called “Make it Happy” and introduced in an ad spot during the Super Bowl, Coke invited people to reply to negative tweets with the hashtag “#MakeItHappy”.
The idea was that an automatic algorithm would then convert the tweets, using an encoding system called ASCII, into pictures of happy things – such as an adorable mouse, a palm tree wearing sunglasses or a chicken drumstick wearing a cowboy hat.