Recently available, jclouds is an open source multi-cloud framework for Java.This release is focused on choice. Choice of cloud providers and choice in tooling to manage them. Inside the jclouds distribution, you will find 15 service choices, including EC2, Atmos, vCloud, Azure, and Rimu Hosting. You can choose to use these apis directly, or use a multi-cloud abstraction like BlobStore or ComputeService. You can also use jclouds via Ant, and other APIs.
http://code.google.com/p/jclouds/downloads/list
