XML.com: Amazon's Web Services and XSLT
Amazon Web Services (AWS) provide two ways to get XML versions of the information that Amazon's customers ordinarily get from HTML web pages: a SOAP interface and a REST interface. It's nice to see the pains that Amazon takes to make it clear that, when it says "web services" it doesn't just mean SOAP-based web services, but REST too. According to Jeff Barr, Amazon's web services evangelist, 80% of the developers using AWS prefer the REST interface.