Ubuntu on Amazon EC2

Ubuntu Server Edition on Amazon – Beta programme now open

Ubuntu Server Edition on Amazon gives you the power of Ubuntu combined with the flexibility of Amazon’s cloud computing service. Ubuntu’s modularity, virtualization capabilities, range of applications and optimised performance make it the perfect solution if you’re deploying applications on Amazon’s Elastic Computing (EC2) cloud.

http://www.ubuntu.com/products/whatisubuntu/serveredition/features/ec2

https://help.ubuntu.com/community/EC2StartersGuide