Use PayPal IPN to automate delivery of digital goods (mp3, ebooks, pdf, graphics, videos and so on) to customers. Sell physical goods as well as digital downloads. Has a number of built in shopping cart front ends including an AJAX shopping cart system. Buy buttons may also be created by hand to easily integrate into existing web pages. File location is hidden and cannot be deduced. Downloads are limited by time and number. Sales are recorded. Associate many downloads files with each product. Checks made on transaction to prevent fraud and spoofing. Email all customers or email those who have purchased a particular product. Simple to install PHP/mySQL system.