Rsync to S3 is a service which combines EC2 and S3 to provide a bandwidth efficient S3 based backup mechanism. It takes advantage of the free bandwidth between EC2 and S3 to overcome the limitations of S3 for rsync backup.
WeoCEO is designed to provide a constant front end to Amazon EC2 / S3 services. It provides stable IP, load balancing and DNS management to ensure your app stays online.
An article describing a system that uses client side load balancing in a Web application. Voxlite is the example application built on Amazon EC2 and S3.
3tera provide a grid platform to deploy "virtual appliances" on a "virtual datacentre" built on top of commodity hardware, similar to Amazon's EC2/S3.