Nullpomino

NullpoMino is a cross-platform, open-source fan game written in Java providing three versions: One using Slick, another using sdljava, the last using Swing. The game also simulates many Tetris games, as well as the TGM series and a few fan games, and also contains a utility for creating your own custom rotation systems. NullpoMino is one of the few Tetris games, official or fan-made, with a truly cross-platform online versus mode.