Holders of the cryptocurrency Ethereum had spent more than $2 million on virtual kittens by Sunday night, bought and sold over a new blockchain-based game called CryptoKitties.
The craze for the virtual cats — whose exorbitant valuations are reminiscent of pre-crash Beanie Babies in the 1990’s — mushroomed within days of the game’s launch on Nov. 28, TechCrunch reports. According to a third party site that monitors their sales the most expensive kitten so far was bought Sunday for $117,712; the mean price of a virtual kitten is currently a little less than $90.
CryptoKitties function much like the cryptocurrencies used to purchase them. They are not stored in a centralized database and because each one is a unique, immutable object traded over blockchain, they can continue to exist as tradable objects even if their creator AxiomZen were to go bust.
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Besides being cute and furry, one of the few ways CyptoKitties differ from their coin equivalents is that as well as purchasing them directly from the issuer, players can breed them to create “genetically unique” offspring, which can in turn be bought and sold. Launched with an initial 100 “founder kitties,” each specimen can “sire” a new kitten and sell it to other users. AxiomZen takes a 3.75% cut of every transaction in this secondary market.
CryptoKitties is now so popular that it accounts for about 15% of all Ethereum network traffic, according to TechCrunch. That’s more than the roughly 8% taken up by the next most popular smart contract on the network: a decentralized coin exchange called EtherDelta.