MiniVend is a freely-redistributable database retrieval and display application focused on e-commerce. In other words, a high-end and powerful shopping cart. It serves any number of catalogs via the World Wide Web, allowing users to select items for placement on their shopping list, or cart, and then buy them by filling out an order form.
MiniVend supports Secure Sockets Layer (SSL), PGP/GPG strong encryption, and online payment services to improve security. It is designed never to write an unencrypted credit card number to disk.
MiniVend has a host of features -- a partial list is available at its web home page:
http://www.minivend.com/
A more complete list is in its documentation, available via links from above.
A full list can only be seen by examining its source code. 8-)
MiniVend is written and maintained by Mike Heins, but much credit goes to Andrew Wilcox, who originated Vend and created many of the underlying algorithms.
MiniVend is freely redistributable under the GNU General Public License, a copy of which should come with every MiniVend package. Basically this means that you can use it for commercial or non-commercial purposes for free, but you you have certain responsibilities if you modify and/or redistribute it. See the GNU GPL for more information.