From Hard Drop Tetris Wiki
GinT is a Tetris-like game that is implemented in LSL scripting language within the 3d World of Second Life. Features include hard drop and a two player competitive mode where players can wager on games in "Lindens", the micropayment currency of Second Life which can be bought and sold for US dollars.
GinT may be the first implementation of Tetris with a built in wager feature. Some Tetrinet servers also have this type of wager system. At skilljam.com, players can play their game Jamtris against other players for money.