Steam is one of the most popular gaming-related platforms in the world these days. As a result of that popularity, Steam is also attracting a bunch of unwanted attention from hackers and phishers, According to details released by Valve, roughly 77,000 Steam accounts get hijacked on a monthly basis. Even though Valve makes two-factor authentication for in-game item sales mandatory now, blockchain technology could play a major part in creating a better solution.
http://bitcoinist.net/valve-introduce-blockchain-based-authentication-steam-users/