Amazon's DevPay service graduated recently from beta to general availability, which means that it is now easier for companies in the United States to build a business based on Amazon Web Services.
DevPay allows you to sell your own applications based on Amazon's storage (S3) and computing (EC2) services. You set the price that customers will pay and the service then takes care of the billing and account management tasks, leaving you free to concentrate on your application.
Unfortunately you still need to have a U.S. bank account to register for a DevPay account. From the FAQ:
Sellers of Amazon DevPay applications must be able to do business in the United States. Funds earned through the sale of Amazon DevPay applications can only be withdrawn to U.S. bank accounts.
So it looks like those of us outside the U.S. will have to remain patient.