The Apache HTTP Server Project is a collaborative software development effort aimed at creating a robust, commercial-grade, featureful, and freely-available source code implementation of an HTTP (Web) server.
SpamAssassin runs on a server, and filters spam before it reaches your mailbox. It has been used by nearly every known mail delivery system. Install it yourself today...
GNU Zile (Zile Is Lossy Emacs) is a lightweight Emacs clone. Every Emacs user should feel at home with Zile.
Component oriented framework for creating dynamic, robust, highly scalable web applications in Java.