Refereum is an Ethereum project which lets you win rewards by watching Twitch streams. You can enter the website (refereum.com), login on a Twitch account, link an Ethereum adress and win TICKETS. 

Once you win TICKETS, one per minute, you access a raffle that happens every few hours. People accumulate as much tickets as they can, and then a ticket is picked an the winner adress is rewarded. Usually a hundred dollars. 

The stream and the earning of tickets isn´t stopped when you switch tabs so as long as you have the browser opened you could be winning tickets. 

Is an interesting project but it depends on the gaming industry for its success, which right now is a great thing since the eSports market has half a billion audience. 

Refereum was created at the end of 2017, and has escalated it´s value to 0.01 USD. 

If you are already watching Twitch streams it may be a good idea to try it out. The web lets you choose between top games like Fortnite, Destiny, CoD...