Twitter

Earlier this month an American student was arrested in Egypt while trying to photograph a demonstration. The student used his mobile phone to send a message to Twitter simply stating "Arrested". His Twitter readers were then able to contact the US Embassy and the media to draw attention to his case.

The TechCrunch article about this has some interesting comments. Everyone seems to agree that this is fantastic PR for Twitter, especially with the outages and personnel turnover going on at the company right now. There also seem to be a lot of Twitter haters.