Abyss Web Server
Abyss Web Server enables you to host your Web sites on your computer. It supports secure SSL/TLS connections (HTTPS) as well as a wide range of Web technologies. It can also run advanced PHP, Perl, Python, ASP, ASP.NET, and Ruby on Rails Web applications which can be backed by databases such as MySQL, SQLite, MS SQL Server, MS Access, or Oracle.
htaGen generates user files required for protecting directories on Apache web servers using a .htaccess file.
(shareware) HTTP BenchMark is an easy-to-use tool for checking web servers Bandwidth from client side.
The MAMP is a free, open source utility that enables Mac OS X users to install Apache server, MySQL, PHP, eAccelerator and PHPMyAdmin with ease.
mod_rendezvous adds Apples Rendezvous support to Apache.
Xerver is a free GPL web and FTP server.