mod_ssl
Secure socket layer module for Apache. Acts as an interface for SSLeay.
OpenSSL
The OpenSSL Project is a collaborative effort to develop a robust, commercial-grade, fully featured, and Open Source toolkit implementing the Secure Sockets Layer and Transport Layer Security protocols with full-strength cryptography world-wide.
The Apache Software Foundation
Main site of this top rated internet web server.
The Caudium Webserver Project
A GPLed Web Server that is FREE to use. It is extensible and very easy to design web sites with dynamic pages.