Quote from Sivak:

Hey folks. Thanks to the help I got, I have a pretty clean rom of a functional Columns game. Right now, things are simple and only 8 blocks are in the rotation of what you get (one of which being the magic jewel), so things won’t be too challenging. Though you can see how the engine works currently.

To check it out, go to: http://www.nintendoage.com/media/_usermedia/attachments/COLUMNS%2Ezip

http://www.nesdev.com/bbs/viewtopic.php?t=4108