MapBox is a suite of open source tools to create beautiful custom maps in Amazon's cloud
Elastic Utility Computing Architecture for Linking Your Programs To Useful Systems - is an open-source software infrastructure for implementing "cloud computing" on clusters- aka "open source ec2"
We've created a pre-built AMI that makes it easy to get started with Drupal on EC2. Just start it up and you're ready to go. And it works with any version of Drupal you'd like.