There are a few AMIs available: http://www.daemonology.net/freebsd-on-ec2/

Yes, this if for their CDN/edge system. They run their cloud architecture on EC2. There was a very interesting talk about this on EuroBSDCon (http://2013.eurobsdcon.org/eurobsdcon-2013/talks/#AlistairCr...), but I can't seem to find the video.

I believe these are the boxes you can install if you're an ISP to cache the most popular content - hence the talk of 100TB of hard drives etc.