To quote Jon Stahl: 

"bottom line: $288/mo for a 7.5GB server, plus trivial storage/bandwidth charges, $72/mo for a 1.5 GB server"

SteveM in the #plone irc channel, suggested that we consider how prices for using Amazon compares with other hosting options.

So that's what this page is for.

Jon Stahl reminded me about this calculator

http://calculator.s3.amazonaws.com/calc5.html

Add scenarios where you can benefit from always on.