Another week, another story about a retro game fetching silly cash on eBay – though thankfully, the relatively low profile of this one means you probably won’t face a price spike amongst non-clued sellers. The auction was for a NES prototype of Chip’s Challenge, an unreleased conversion of the puzzler that gained its fame on the Atari Lynx, and ended at $4,123.99.

The prototype, for which no ROM dump currently exists, shows noticeable differences to its counterparts on other platforms. Notably, it is not a finalised version intended for retail, exhibiting level skip functionality that would not have been present in the complete game At present, there’s no information on whether or not the new owners of the cartridge intend to preserve this piece of gaming history – fingers crossed, though.

If you’re curious about the sorts of people that pay such huge amounts of money for these unreleased games, our Gaming Illuminati feature interviewed a number of them about their unusual corner of the hobby. It ran in Retro Gamer issue 34 and issue 35 – click the links to pick up digital copies via GreatDigitalMags.com.