First released in the US in 1995, the original PlayStation is remembered fondly for its diverse library of games and 'advanced' gaming system, for the time at least.
But, low print runs and limited availability make some of its titles amongst the hardest in the gaming world to get your hands on.
As with most things on the resell market, the rarer a game is, the higher its value.
As a result, hardcore fans are often willing to part with some serious cash in order to add certain PS1 games to their collections.
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A copy of 1996's Batman Forever Arcade, for example, sells for up to $155.
And Castlevania: Symphony of the Night, which was released in 1997, could bag you $590.
But, there's one iconic game from the 1990s that could earn you much more.
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Survival horror game Resident Evil sees players control Chris Redfield and Jill Valentine, members of the S.T.A.R.S. elite task force, as they try to escape from a mansion infested with zombies and other terrifying creatures.
While the game faced some criticism for its corny dialogue and clunky controls, its fascinating plot and solid graphics made it an international bestseller.
It became the highest-selling PlayStation game following its release in 1996 and by December 1997, had sold an estimated 4 million copies worldwide, launching a word-famous franchise.
With so many Resident Evil copies sold, it's not too hard to find on resale sites. Unless you're looking for a sealed one, that is.
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So few unopened copies of the game exist that they're unsurprisingly very expensive and will likely get more so as time goes on.
The Gamer names it as the most expensive PS1 game to buy sealed and unused and a copy is currently going on eBay for a whopping $1,799.
However, there's a limited edition run of another game that consistently sells for upwards of $2,000.
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Elemental Gearbolt is a light gun shooter game that was first released in Japan in 1997 and in the US a year later, in which two powerful beings try to defeat the tyrannical leader of a sci-fi fantasy world.
If you happen to own a copy of the US version of the game, you can expect to sell it for around $200. A sealed version of the Japanese release could bag you up to $300.
But, an extremely limited run of the game is even more desirable. The Assassin's Case edition features the game sealed in a briefcase alongside a golden GunCon and memory card.
Just 40 copies of the game were produced in total which were exclusively available as a prize at 1998's E3 tournament, making it one of the rarest, and most expensive, games out there.