Tetris Friends Online Games offers a wide range of browser based Tetris game modes.
Single-player game modes include: Marathon, Sprint, Ultra, Survival, 1989, and N-Blox. Multiplayer game modes include: Battle 2P, Battle 6P, Sprint 5P, and the highly unique Rally 8P. You can also play real-time Tetris against up to 5 other players in Tetris Arena (registration required).
"One of the 100 best PC games of all time" - PC Gamer
"You may very well think you've played enough Tetris. But have you played it with friends?" - Kotaku.com
"Designed as a massive collection of the best free Tetris games available, this web game collection gives gamers a huge number of ways of playing this classic title." - IGN.com
November 22, 2008