Bill Joy is co-founder Sun Microsystems (and is now a partner at the VC firm Kleiner Perkins Caufield & Byers). In an interview with Business Week, he said that the potential of the green technology field is enormous, and it will be where the next Google will be found. Here is Bill Joy quoted in the interview:
[Kleiner partner] John Doerr said to me: "Are we going to have any more Googles?" And I said: "You're damn right we are, because we are at the point of new wealth creation when it comes to green technology." John used to say Google is the greatest legal creation of wealth, and I think the greatest legal creation of wealth today is in the green area -- not just in the U.S. but in the developed world. We have been looking at a lot of things related to new fuels, such as ethanol, fuel cells, advanced battery technology, and new ways of using biotech to make fuels.... There will be an enormous amount of new [green] technology, new wealth, and we are trying to create the Googles, the Microsofts of the new era. [Even] the garbage stream has a high value.