What are CryptoKitties and why do some cost thousands of dollars?

Would you pay for a virtual kitten? Apparently many people will and have, through the online game CryptoKitties, which is the latest craze in the world of cryptocurrencies.

Among the "cattributes" of CryptoKitty No. 209107 are violet highlights and googly eyes. And it can be yours for 7 ether, or about $4,100. Yes, you read that right—this digital cat is for sale using the blockchain technology Ethereum for more than $4,000. And while you can get one for as little as a buck or two, some have sold for more than $100,000.

CryptoKitties cofounder Bryce Bladon explains that the virtual cats are digital collectibles.

"Each cat is one of a kind, 100 percent owned by you," Bladon says. "Can't be replicated, taken away, or destroyed."

He says the idea was to put a furry face on the sometimes hard-to-understand concept of blockchain technology, i.e. what enables cryptocurrencies, such as Ethereum and bitcoin.

"Basically, at the end of the day we realized for this technology to realize its potential it needed to be used by consumers," he says.

And what better to draw in regular people than cats. Bladon likens the CryptoKitties to collectibles like Beanie Babies or baseball cards but there is one big difference.

"Unlike a traditional collectible, you can breed two of them together to create a brand-new, genetically unique offspring," he says.

But what's the appeal?

"It's based on a really important concept: I can have a digital file that's authentic and one of a kind," says tech expert Shelly Palmer, who sees CryptoKitties as the first step towards a bigger world of digital art.

"This is a baby step in the beginning of authenticated digital art that you can own, that has a value, that you can prove is unique," Palmer says. "And you don't need an art dealer to tell you."

But while each CryptoKitty is unique, very few are rare. Bradon says right now about 800,000 CryptoKitties exist with a potentially unlimited number of offspring. And unlimited supply means most of the cats won't make you rich.

So experts say that if you're thinking of getting into CryptoKitties, do it for the love of the game and a little education—not the money.