I would like to see one day a real game economy with the bitcoin currency. The game should provide will value to play it and have fun in the same time. The game should provide challenge, include crafting or you sell the stuff or trade with the other players.
Well, you can try make trades and lend some money on poloniex
If you have a good imagination, you can work with it like it was a game... You have a lot of options of altcoins to buy and sell and try to make some profit, btw you have to invest.