Starting today, Amazon is making available its sophisticated storage network to developers, for a fee. If your only kind of interactions with Amazon were online transactions to buy goods, you may have missed that the company is already offering numerous Web Services to developers. Wondering why?The charter of Amazon Web Services is to provide developers with building block technologies that help them innovate. explains Adam Selipsky, VP of Product Management and Developer Relations for Amazon Web Services. The new storage service, S3, which stands for Simple Storage Services, is the logical extension to the services that Amazon is already providing. What makes S3 different from any other storage service I know of, is that you can only store or retrieve data via API, using REST or SOAP interfaces.You can store objects of up to 5GB in a single operation, but Amazon puts no limit to the total amount of storage you can use. The cost involves a transfer fee and a monthly storage fee. For example, moving 100GB to S3 would cost a one time fee of $20, plus a storage fee of $15 per month.Obviously a dedicated local drive on your server would cost less, but not if you try to emulate the reliability and the ubiquitous nature of data stored on S3.I asked Selipsky if it’s possible that users will in the future exceed the overall capacity of the systems supporting S3 but he doesn’t seem concerned. “We think that developers are going to build all sorts of application on S3” says Selipsky. “The only thing I am sure of is that we will be surprised by the way people innovate”.