Tetrinet is an old spinoff of the classic tetris game that has been making a comback recently at UMass. To compete against other people at UMass you first need to download the client here. If you can not open the file you need to also download winzip.
After downloading and extracting the game, goto client settings, pick a nick, and for the server ip enter: urgo.org and hit connect.
After you successfully connect, click on the partyline to chat with others on the game, or show fields to play the game.