Tools for Super Tux Kart server operators
FreeCS is a free-software reimplementation of Counter-Strike 1.5.
Suite of utilities to make running a Lugdunon server easier
Suite of utilities to make running a Linux Teeworlds server easier
Suite of utilities to make running a MekWars server on Linux easier
Makes running a PSO server on Linux easier
Free MMORPG
Utilities for running the Pokemon Online server on Ubuntu
JAVA websocket implementation for a bomberman-like game
Simple meta-server for locating other multiplayer servers
A Simple and Easy to Use User Interface for Private Bukkit Servers
GraphOX is awesome
Tools for installing and setting up dedicated Battlefield servers
A multiplayer First-Person-Shooter game built in Java 3D