atari2600land has updated his single and two player simultaneous play variant of a very well known Russian block game.

Release notes:

Hi all, apparently the score was all wacked out in two-player mode when player two got a line or more. I fixed that. Tell me if you run into any bugs in this version, especially the two player mode.

http://www.atariage.com/forums/topic/153710-2600tris/page__st__150