1) Freeware game 
Blocktrix is a free, online, multiplayer, puzzle game based on TetriNET and was created in 2000 by StrikeLight. It was developed as an update to the official TetriNET 1.13 client after the original creator, St0rmCat, created a new version to the game entitled TetriNET 2, which included major changes to the TetriNET client such as not allowing priv...