Paid EMIs from Amazon EC2
Paid AMIs allow AWS developers to charge other Amazon EC2 users for the use of AMIs they have created and shared. Sellers of AMIs set the price, and their customers then purchase one or more AMIs and are billed through Amazon.com for their use of these paid AMIs.
Right now, only a select group of people can create paid AMIs, but hopefully they will open it up to more in the future.