In a nutshell: The big three console makers—Microsoft, Sony, and Nintendo—are rivals, but there was a time in the late 80s when the two Japanese firms came together to create a SNES with a CD-ROM drive called the Nintendo Play Station. The project was canceled following disputes between the companies, but a prototype remains in the hands of one lucky person, who is now putting it up for sale.

Following the cancelation of the console in 1991, Sony created its own PlayStation machine in 1994. But there were some prototypes of the first 'Play Station' floating around.

In 2009, Terry Diebold paid $75 for some items in an online bankruptcy auction. The abandoned property came from a former Sony executive, and it wasn’t until 2015 that Diebold’s son, Dan, found the console in the family attic. After discovering a Reddit thread about the Play Station, he realized the value of the machine, which is believed to be the last prototype in existence.

Since then, Terry and Dan have been touring the world, showing off the Nintendo Play Station at game expos. Speaking to Kotaku, Diebold said: “I’ve put a lot of work into this by traveling with it and we have made nothing on it. Every trip that we... have taken with it has cost us money out of pocket.”

With the pair no longer wanting to lose money, the console will be sold in an online auction run by Heritage Auctions, which sold a sealed copy of Super Mario Bros. for over $100,000 at the start of the year.

The auction will begin on February 27, and there’s no reserve price for the Nintendo Play Station. Diebold says he already turned down a $1.2 million offer from a person in Norway, so expect the final selling price to be very, very high.

“In the case of this particular item, since it’s never been sold at public auction before, there’s really no way to tell,” said Valarie McLeckie, Heritage’s director of video games.