9 Very Rare (and Very Expensive) Video Game Cartridges

If you've ever collected baseball cards, comic books, stamps, or maybe those limited edition commemorative plates, you understand the concept of the "Holy Grail" item. It's that last, hard-to-find, incredibly rare, usually expensive piece that you have to have before you can officially say your collection is complete. If you're a collector of vintage home video game cartridges (or "carts"), sometimes that can mean paying a pretty penny for the pièce de résistance.

Nintendo Entertainment System (NES)

Back in the day, everyone had a Nintendo. Due to the console's popularity, there are a large number of collectors willing to pay the equivalent of a new car for some of the systems' very rare carts.

1. Stadium Events

Stadium Events recently made headlines with two high-profile eBay sales. A North Carolina woman was cleaning out her garage and found an old Nintendo and a handful of games, including Stadium Events. She put them up on eBay without high expectations and was amazed to see the bids steadily climb up to $13,105 by the time the auction ended on February 13, 2010. While the game itself is valuable, the winning bidder was most interested in the cardboard box it came in. Since most kids threw the box away after tearing open a new game, intact boxes for any game are really hard to come by, but especially so for Stadium Events. Empty Stadium Event boxes have been known to sell for $10,000 alone.

After hearing of the success of this eBay seller, a man in Kansas dug up a factory-sealed copy of the game that he was just about to donate to Goodwill because he thought it was pretty much worthless. However, his game became only the second known sealed copy in existence. He'd purchased the game in 1987, but could never find the Fitness mat to go with it. It was still sealed because he'd meant to return it. When his eBay auction ended on February 26, 2010, the game sold for an amazing $41,300.

The same game repackaged by Nintendo, World Class Track Meet, generally sells for less than $3 on eBay.

2. 1990 Nintendo World Championships (Gray and Gold Editions)

Price Range: Gray: $4,000 - $6,100; Gold: $15,000 - $21,000
Why So Expensive?: In 1990, Nintendo held a 30-city gaming tournament to find the best player in the world. Players had to get the best score in demo versions of three games "“ Super Mario Bros., Rad Racer, and Tetris—all within a six-minute time limit.

At the end of each city's tournament, the winners of each of three age groups were given special gray Championship cartridges exactly like those used in the competition, which means only 90 of these cartridges were distributed. The gold version was sent out to those who won a promotional contest in the pages of Nintendo Power magazine. Only 26 gold games were produced, so they're especially hard to find and command a higher price today.

3. Nintendo Campus Challenge

Most copies of the game were destroyed after the competition ended, but one Nintendo employee kept his cart and sold it to Rob Walters at a garage sale in 2006. This garage sale is legendary among retrogamers, as Rob bought all kinds of NES Holy Grails for only $1,000. By the time he re-sold everything, he'd made 50 times that. Part of that $50,000 was the Campus Challenge cartridge, which went for $14,000. Shortly after, the buyer of the cart turned around and sold it on eBay for $20,100. As far as anyone knows, it's the only copy of the game in the world.

ATARI 2600

The wood-grained grandpappy of home video game systems still has a rabid fanbase. And those Atari enthusiasts wish to recapture the days of playing these simple games while drinking Pepsi from glass bottles and listening to Foghat.

4. Atlantis II

Because this version was not mass produced, its pretty rare today. But if you find a copy of the original Atlantis at a garage sale, it might be a good idea to pick it up anyway. The competition cart had the exact same colorful label of the regular Atlantis, but had a small, white sticker slapped on the front that read "Atlantis II." The label was easily peeled off, so a quick Google search will show you how to determine if you bought a $3 Atari game or a $6,000 one.

5. Air Raid

6. Star Wars Ewok Adventure

The game was shot down by Parker Brothers' marketing department, who felt the controls were too hard to master, so it was never produced. The game's designer, Larry Gelberg, gave the one and only known prototype copy to a friend's son, who later sold it for $1680.

Neo Geo

The Neo Geo, first released in 1990, was always a bit of a niche home video game console, mainly because of its price—the system was $649 and games started at $200. However, those who had a Neo Geo really loved it, so the collectors' market has remained strong.

7. Kizuna Encounter

Why So Expensive?: One of the main games that all Neo Geo fanatics are looking for is a particular version of Kizuna Encounter, a 1996 fighting game similar to Mortal Kombat or Street Fighter. The game itself has received solid reviews, but isn't groundbreaking by any means. However, it was produced in such small quantities for the European market that collectors speculate fewer than 15 copies were made. The Japanese version, which is exactly the same except for different packaging, is fairly common and sells for about $50.

8. Ultimate 11 (AKA Super Sidekicks 4)

In late 2009, a private sale was reportedly made between two members of the collectors' forums at neo-geo.com. The buyer paid an astonishing $55,000 to acquire both Kizuna Encounter and Ultimate 11. The original owner purchased the games around 10 years ago, when Kizuna was selling for $500 and Ultimate for $400. The new owner has said he will not sell them, even if he were offered $100,000.

9. Metal Slug

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