withinweb

PHP-eSeller is a PHP / mySQL application that you install onto your web site and interacts with PayPal or Google Checkout to automatically sell digital files.  When the customer makes a purchase, the process of delivering the files is automatic and so provides a 24 /  7 solution.

Once PHP-eSeller is purchased, there are no additional fees for the application, except fees that you pay to PayPal and Google Checkout.  The purchase of PHP-eSeller is a one time purchase.

It can be used to see any type of digital download.  See

http://www.withinweb.com/phpeseller/usersites.php

which lists some of the sites that are using the application.