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.
UProxy is a proxy for UDP protocols. UProxy was initially designed to allow users to play Unreal Tournament matches over the Internet on computers sharing a dial up connection. It could also be used by any client-server application that uses the UDP protocol and doesn't require clients to bind a fixed port. UProxy should run under Windows, Linux, or any OS which supports BSD sockets.
ServerSpyIRC is a Perl IRC bot (based on Net::IRC) which can retrieve information about Quake2, Quake3, and Halflife/CS online game servers. It supports many search functions, scanning of posted IP addresses, simple clanwar outputs, user management, bookable functions, and server lists.
codstats.tcl is an eggdrop Tcl script that communicates with a Call Of Duty (COD) server to allow interaction between the game and an IRC channel. It can accept commands on an IRC channel to display statistics from the COD server. It can mirror in-game speech in an IRC channel and vice versa. It can also display server joins/parts on an IRC channel and periodically announce the number of players on the server.