Amazon recently announced a new web service called CloudFront, here's what they have to say about it:
I think making these services available to small businesses is going to level out the playing field when it comes to delivering content using the kind of bandwidth necessary for a pleasurable site interaction. Fast load times have been a hallmark of larger websites that have been using traditional content delivery network services such as Akamai. It will interesting to see the new face of cdn's in the next five years. We might seen a significant amount of consolidation, and value added resellers similar to the existing Amazon Associates program.
Amazon CloudFront is a web service for content delivery. It integrates with other Amazon Web Services to give developers and businesses an easy way to distribute content to end users with low latency, high data transfer speeds, and no commitments.
Amazon CloudFront delivers your content using a global network of edge locations. Requests for your objects are automatically routed to the nearest edge location, so content is delivered with the best possible performance. Amazon CloudFront works seamlessly with Amazon Simple Storage Service (Amazon S3) which durably stores the original, definitive versions of your files. Like other Amazon Web Services, there are no contracts or monthly commitments for using Amazon CloudFront – you pay only for as much or as little content as you actually deliver through the service.