The following is a great 2004 BBC documentary about Tetris, the man who created it, and the lengths that several companies went to in order to procure the rights to distribute it. Tetris - From Russia With Love:
Alexey Pazhitnov, a computer programmer from Moscow, created Tetris in 1985 but as the Soviet Union was Communist and all, the state owned the game and any rights to it. Who procured the rights from whom on the other side of the Iron Curtain became the basis of legal wranglings and lawsuits; the Atari/Nintendo battle over Tetris wasn’t settled until 1993. There’s an abbreviated version of the story, but the documentary is a lot more fun. A rare copy of the Tengen version of Tetris, which was pulled from the shelves due to legal troubles, is available on eBay for around $50.