If you’ve been paying attention these past few years, you probably see that the future of video gaming is digital. That’s the way things are trending, with app stores raking in money and digital sales of PC and console games going through the roof. The gaming machines of the future won’t even have disk drives. So why are old video game discs and cartridges more valuable than ever?

Because that’s how collectibles work. Their value goes up as they become more rare. Here are seven retro video games that are worth big money today.

1. The Misadventures of Tron Bonne

Platform: PlayStation
Sells for: $235 – $440

It’s kind of crazy how many Mega Man games Capcom has released over the years. The list, which you can find on Wikipedia, goes on and on. In fact, there are no fewer than seven different series of Mega Man games. Among those is Mega Man Legends, a group of role-playing games from the original PlayStation era. The games are quite highly regarded, even today — assuming you can get past their breathless anime style.

The second game in the Mega Man Legends series was itself a kind of spinoff. It was The Misadventures of Tron Bonne, a prequel that stars Tron Bonne, a member of a family of air pirates in the Mega Man Legends series.

Perhaps because it was a spinoff of a spinoff, Capcom didn’t print many copies of the game. That’s why it sells for relatively big bucks compared to other PlayStation titles. Thankfully, if you want to see what misadventures the title heroine got into without dishing out hundreds of dollars, you can buy it on the PlayStation Network for $6.

2. Earthbound

Platform: Super Nintendo
Sells for: $160 – $2,500

A boy and his friends go on a journey around the world to save all of humanity from aliens. That’s the premise behind this cult classic, which wasn’t very popular in its heyday, but people have come around in the years since.

Even if you’re unfamiliar with the game itself, there’s a good chance you know its main character, Ness, who has appeared in numerous Smash Bros. games over the years.

One interesting thing about Earthbound is that it came in an enormous box, thanks to the big full-color walkthrough Nintendo packaged with it. The game cartridge itself usually goes for around $200 nowadays, but if you still have the box and the guide (particularly if you never tore out the page of scratch-and-sniff cards), you could be sitting on several thousand dollars worth of collectibles.

On the other hand, if all you want to do is play the game, you don’t have to drop hundreds of dollars on it. It’s available on the Wii U Virtual Console.

3. Metroid Prime and The Legend of Zelda: Wind Waker Combo

Platform: GameCube
Sells for: $160 – $1,500

You might have played both of these games individually, but chances are you don’t have a copy of this collection of two classic Nintendo GameCube games. That’s because it was released as part of a special Gamecube bundle that was only sold during the holiday season of 2005, which was four years after the console debuted.

This limited edition collection came with two discs, one for each game. Although the discs were exactly what you’d get if you bought the games separately, it’s the unique case that makes it valuable. That, and the limited number of copies Nintendo printed.

4. Dead Space Ultra Limited Edition

Platform: Xbox 360
Sells for: $350 – $700

Sometimes buying limited editions of games pay off, like with this special edition of Dead Space, the 2008 survival horror game from Electronic Arts. This version of the game comes with the game itself, a hardcover 160-page graphic novel, a DVD of the Dead Space Downfall animated movie, a signed lithograph, a clothing patch, and a 3-D art book.

So why’s it so valuable (besides the obvious cost of the materials included)? EA only made 1,000 copies of it. Watch the unboxing video above to get a first-hand look at the items included in the package.

5. Uncharted 2: Among Thieves Fortune Hunter Edition

Platform: PlayStation 3
Sells for: $1,600

Not only is Uncharted 2: Among Thieves one of the very best games of the PlayStation 3 console generation, but if you have the right version of the game, it could be worth a whole lot, too.

This special edition came with the game itself, a replica of the Phurba dagger that plays a role in the game, a collectible art book, and a collector case that’s been autographed by the development team.

Only 200 of these bad boys were made, but you couldn’t buy one in stores. All of them were given out as prizes for a contest that ran when the game first came out in 2009. If you weren’t lucky enough to win one, prepare to spend big bucks on eBay to get your hands on one now.

6. Stadium Events

Platform: Nintendo Entertainment System
Sells for: $1,800 to $8,000

While this game would have been a blip on the radar if it had been made widely available, Stadium Events has become famous for being the rarest officially licensed NES game of all time.

The reason? It came with a floor pad peripheral that Nintendo bought the rights to shortly after the game’s 1987 release. That meant publisher Bandai had to recall the game almost immediately after its debut. It all happened so fast that only about 200 copies were sent to stores in the U.S., and only 10 to 20 copies have been spotted in the wild ever since. That’s why it’s worth such a pretty penny.

If you want to play this game now, I hope you’re rich. Search eBay, and you’ll likely find someone trying to sell it for upwards of $15,000.

7. Nintendo World Championships Gold

Platform: Nintendo Entertainment System
Sells for: $27,000

As you may have noticed, any game that had a limited run is likely to be worth money. That’s what’s at play with Nintendo World Championships Gold, a cartridge so rare that only a couple dozen of them exist in the whole world.

In 1990, Nintendo hosted a Nintendo World Championships competition that toured through 29 cities in the U.S. The goal was to find the most talented gamers in the country. To do so, Nintendo made special cartridges that contained mini-game challenges from Super Mario Bros., Rad Racer, and Tetris. Contestants would play through the challenges, trying to rack up the highest score possible in a limited amount of time.

All 90 Nintendo World Championships finalists received a copy of the cartridge in the standard gray color of most NES games. Nintendo Power magazine ran a separate competition that awarded 26 winners with a special gold version of the cartridge. Since so few of those cartridges exist, it’s a hot commodity in the collector community. If you want one, you’d better start saving.

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