http://www.eucalyptus.com/
On premises cloud computing platform, with an open source angle. Don't fully understand it.
http://www.rightscale.com/
A platform to manage cloud computing resources, deployments, and so on. Essentially a simplified front end for AWS as far as I can make out.
http://cloudcontrol.com/
Scalable PHP PaaS service. Based on the concept of "boxes", which handle 2 simultaneous requests each, and can scale up and down dynamically. So 12 concurrent requests equals 6 boxes. Strange, but potentially cost effective for traffic peaks.
http://orchestra.io/
PHP PaaS provider based in Ireland, acquired by Engine Yard.
http://www.pyrosoft.co.uk/blog/2010/10/27/import-your-own-rsa-ssh-key-into-amazon-ec2/
How to get custom RSA SSH keypairs into EC2. There is one region missing from this post.
http://simol.codeplex.com/
A .NET object-persistence framework for Amazon SimpleDB written in C#. Supports .NET-style parameterized selects; asynchronous operations; lexicographical date and number formats; integrated caching; full-text search, and more.
