Amazon's recently released (which it calls EC2 and is still in beta) for the first time brings to the masses grid computing and utility computing --- the ability to buy server power in the same way you now buy electricity or water.

In essence, you pay 10 cents per virtual server per hour, plus bandwidth costs, and you do with that power whatever you want. While it's not quite as simple as turning on your water tap, it's the same basic idea. You pay only for the processing power you use, and how much you use is entirely in your control.

IBM, HP and Sun already sell computing power on demand, but they sell primarily to large enterprises, and on a very big scale. Amazon, on the other hand, sells to small and medium-sized businesses, as well as to large enterprises, and does it via unique technology that builds on previously released Amazon middleware services.

Not everyone agrees that the same company that offers 40 percent off best-sellers should try to become a big-time IT provider. But Amazon has always believed that books were only an entree into selling far more sophisticated goods and services. Can it succeed? We'll take a look inside the technology, then talk to the Amazon executives in charge of the service, which may give some hint as to whether it will pay off.

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