Suresh Ponnusami sat back on his porch by the road south of the Indian textile town of Tirupur. He was not rich, but for the owner of a two-acre farm in the backwoods of a developing country he was doing rather well. He had a TV, a car, and a maid to bring him drinks and ensure his traditional white Indian robes were freshly laundered every morning.

The source of his wealth, he said, was a large water reservoir beside his house. And as we chatted, a tanker drew up on the road. The driver dropped a large pipe from his vehicle into the reservoir and began sucking up the contents.

Ponnusami explained: "I no longer grow crops, I farm water. The