Open-source web server by America Online, multithreaded, Tcl-enabled, massively-scalable and extensible, also features database integration and a dynamic page scripting language (ADP).
A fast and efficient HTTP server that has CGI support (no post support, only get). Ghttpd has a small memory footprint and is capable of handling thousands of simultanious connections. GPL.
Web server that runs on a variety of Unix platforms and is free under the terms of the GNU General Public License. Online user guide, and other documentation.
FTP/HTTP server with modules support. Modules run as separate "looping" processes locally or remotely, and can be configured to run under separate userids.