Katharine Gammon 06.01.12 12:15 AM The Mexican capital is long on rain but short on clean water. A new startup is using the water that comes from the sky to quench the thirst of the city’s poorest inhabitants. Newsletter Get the latest Fast Company stories delivered to your inbox daily. Send I'd also like to receive special Fast Company offers ARE YOU REGISTERED TO VOTE? Register now to make sure you have a voice in the election.