CryptoKitties launches and congests the Ethereum network

On November 28, 2017, Dapper Labs released CryptoKitties, a game for collecting and breeding digital cats, billed as the first consumer application on Ethereum. It promptly went viral, clogged the network with pending transactions, and at its peak accounted for roughly a quarter of all Ethereum traffic, offering an early and humbling demonstration that blockchains scale poorly when people actually use them.