Imagine a massively multiplayer roleplaying game like Runescape or World of Warcraft suddenly converted to VR. Now add cryptocurrency and blockchain, what do you have? The ability to own that bow or staff in your hand. Likely even the ability to trade it for real money, via blockchain.
Some game platforms like Enjin have already built upon Ethereum, but other platforms exist and are actively trying to attract game development. Even Ripple wants in on the action.