We have an increasing number of Gaming Stack Exchange servers for things ranging from Team Fortress 2 to Terraria. I've posted a community wiki answer to keep track of all the servers.
Use the following format:
Game/Program: name of game/program
Address: server address
Password: *password of the server, if it has one**
Host: the user(s) hosting the server
Status: current status of the server. Is the server currently up or down?
Location: region/country the server is located