I've never heard of this, but I thought someone here might be interested. Auction ends tomorrow: http://www.shopgoodwill.com/auctions/Tetris-Plug-and-Play-Game-1-or-2-Players-17143899.html
I've found a couple of these "things" at thirft stores and they are terrible. I would not recommend buying. I've even removed the insides and stuffed them in a NES controller to try and play this clone version of Tetris but alas my efforts were futile.
Ha! Brilliant! I have a set of these lying around somewhere and I always wondered about doing something along those lines...shame it still play so poorly even after the conversion - Jono