You might not think of the Atari 2600 as a system with a lot of hardware expansions but there really were quite a few of them over the years. Some better than others. This particular one is called the RomScanner Command Center and was released by a company called Marjac in 1981.
The RomScanner is impressive looking but it's really a fairly simple device. It's essentially a splitter that plugs into the cartridge port of your Atari 2600 and allows you to insert up to ten cartridges. You can then switch between the games with a simple press of a button instead of removing and inserting another game. To me, it doesn't really seem like it adds all that much convenience. It isn't that hard to change cartridges and if you have more than ten you still would have to sometimes anyway. But the real kicker is the price. It was $49.95 upon release in 1981. An online calculator tells me thats roughly equivalent to $143 in todays dollars.
However, if you want one for your collection it won't be easy to find and you would probably be lucky to pay $49.95 or even $143 today. The original high price and limited utility make these pretty rare.
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