A unique listing went up last week on video game auction site, Game Gavel. It's for a Tengen Tetris prototype, one of three copies in the world, and it's got people dropping money just like the game drops bricks.

According to the Listing Details section of the auction, this supposedly Nintendo-licensed prototype is extremely rare and is "possibly the latest build of Tengen Tetris" before the messy lawsuit that resulted in the game being pulled from shelves a month after its release.

The seller claims to have written for Electronic Gaming Monthly in the late 80's and says that this prototype was given to the magazine for review. He's kept it for 23 years and is now giving collectors a chance to own a piece of history.

The prototype is housed in a modified Duck Hunt cart, which is protected in an acrylic case for display. The current bid, as of this writing, stands at $1,000. The listing requires bids in $50 increments and the reserve price has not been met yet. So if you've got the bucks to blow and a powerful need to own one of these rare carts, give it a shot.

Check out the listing and watch the video below to see what has collectors in a tizzy. And let us know what rare piece of gaming history you'd like to own!