Do you want to know if a website is running on EC2? Use this tool to figure it out quickly.
For the domain z-e-n.co.uk, I found the following IP addresses:
74.81.71.122 - It's not running on EC2 - PTR points to host.dataproserver.net
Some EC2 sites: Some surprising sites that aren't running EC2:
- info.rightscale.com - apparently they only eat some of their own dogfood
- www.amazonaws.com