http://www.ebay.com/itm/Game-Master-.../161431350079?
One of my prized possessions, a prototype of the NES Game Action Replay, labeled here as Game Master Kid. The software on it is different than the released version and behaves more like the save feature in the Game Master Boy, which saw Asia-release only for Famicoms, iirc, and was a great little cheat device. There's an actual menu on it, unlike the non-menu-based released product known as the Game Action Replay, which in itself is extremely rare.


The menu and a sticker on one of the chips on the board indicate Bung basically made this device and wanted to fly under Nintendo's radar in the states and sold the released version of the device under the company name QJ. So, it is a nice little piece of videogame history in that this device alone proves Bung did indeed market their piratey wares in North America, though there was nothing illegal about this device. I'm sure they didn't want to make it totally obvious what they were up to though. So, if you thought QJ with their one-off product was a legit company, you're probably wrong.


In my opinion, it is a better product than the released version because of the menu.


This is not your standard Nintendo prototype in that it is a game, but rather, a cheat device that lets you save your game anywhere. Any game. You slide the device into the NES, the push it down. Then, you slide the game cart in on top of the device and it plugs into the device. If I remember correctly, you use Select+A to save a game, and Select+B to load from where you left off, though I could have that backwards.


http://www.ebay.com/itm/Terminator-2.../161431367227?
Terminator 2 NES Prototype Cartridge. When I got this at the Hollis, NH flea market back in 1997 or 1998 or so, the label was white, but age has made the glue from the label bleed through. It is the only prototype cartridge I ever found in the wild and my first proto I ever owned.


http://www.ebay.com/itm/Gameboy-Game.../161431377747?
Gameboy prototype cartridge of Daffy Duck-The Marvin Missions. Strangely, I bought this thinking this was a Bugs Bunny's Crazy Castle prototype, and it even says GB B.B. on the label over the EEPROM. I was kind of surprised when I found Daffy Duck-The Marvin Missions on it!

http://www.ebay.com/itm/Gameboy-Game.../161431381820?
Gameboy prototype cartridge of Wordtris. When Tetris exploded on the scene back in the day, this was one of the many me-too puzzle games that were released in it's wake to cash in on the craze. Ok enough game, but not as addicting as Tetris.

Thanks for looking!

-Rob