The Red Cross, via a company called mGive, has got the major U.S. carriers on board to allow people to very easily donate $10 to the Red Cross via a simple SMS text message. This led to an "unprecedented mobile response," and has raised over $10 million in relief for Haiti. With text donations peaking at a rate of 10,000 a minute, at $10 per donation, this is raising $100,000 per minute!
