BZFlag is a 3D, multiplayer, tank battle zone, capture the flag game that pits players against each other in a networked environment. It runs on Windows 95/98/NT/2000, Linux, MacOS 10.x, Irix, Solaris, and others. An OpenGL accelerator is highly recommended, but it is playable with 3D in software.
MoxQuizz is a multilingual IRC quiz/trivia script for eggdrops which acts as a game master. A question is posted to the channel, and all chatter is searched for the answer. If something matches an answer or an optional regular expression, the user who said it receives a point. Highscores and an allstars table are managed. Users can ask their own questions, too. A large set of German and English questions are provided, but you can easily run MoxQuizz with your own set. There are numerous fun commands like !hug, !roll, and others.
Ncohafmuta is a text-based chat server that is designed for access from a telnet client. Its purpose is to allow users to communicate in a configurable environment in realtime. It allows users to create accounts with their own settings and optional personal information. Rooms are the basis for communication, whether private or public. Other features include internal email, email forwarding, a configure script for multiple Unices, support for cygwin under Win32, macros, games, a ranking system with access to more commands, ANSI coloring, banning, async DNS, soft/hot-rebooting, detailed, organized logging, and an internal Web server port.