TetriNET is described as 'multiplayer online Tetris game for up to six people, developed by St0rmCat in 1997 that supports team play. The last official version is 1.13. The game was originally developed for Windows and was later ported to other systems'. There are more than 25 alternatives to TetriNET for a variety of platforms, including Android, Windows, Linux, iPhone and Mac. The best alternative is NullpoMino, which is both free and Open Source. Other great apps like TetriNET are Quadrapassel (Free, Open Source), Blockinger (Free, Open Source), Tetris Blitz (Freemium) and Tetris Online Poland (Free).
In Quadrapassel, the GNOME version of Tetris, your goal is to create as many complete horizontal lines as possible. The lines are made from seven different shapes. The shapes fall randomly from the top center of the screen.
Tetris Online Poland (TOP) is an online tetris game where you can play tetris with your friends and tetris experts from all over the world. You can also challenge your own records or train yourself against a bot.
1010! Klooni is a free, libre and open source klooni of the original minimalistic puzzle game by Gram Games. Fill Up the Board: Drag the pieces on the board and try to clear as many strips as you can! Beware though, it is not that easy o:)
Play the popular tetris arcade game on your Mac. This classic puzzle game is easy and fun to play and suitable for kids of all ages. Use the arrow keys on your keyboard to move the and rotate the blocks.
LTris as a tetris clone: differently shaped blocks are falling down the rectangular playing field and can be moved sideways or rotated by 90 degree units with the aim of building lines without gaps which then disappear (causing any block above the deleted line to fall down).