You could start a bitcoin betting site for computer games, like betting for starcraft2, dota 2, League of Legends, Counter Strike Global Offensive, etc.
yes, you can just start a mining company, site for games or betting like all the people here do, but you need you think litle more deeper what people needs as a normal consumer.
If I was you I would do something like ebay or alibaba clone and contact some manufacturers with quite cheap products, because no one wants to spend over 0.1btc to a single product here!!
or you could do a site and we can work together with a little different site all with bitcoin.