TCLink (Perl)
TCLink is a Perl module that processes credit card transactions through the TrustCommerce payment gateway. Features include: An easy-to-use interface; Encryption using SSL and trusted certificates; Fast transactions times (average about 1.2 seconds end-to-end); and Fail-over to geographically distributed servers for extreme reliability. It is licensed under the LGPL. Full source code is included, as well as developer documentation and example Perl scripts.