As if Crypto Tab already wasn't the coolest and easiest way to earn bitcoin for free!! They have made it even easier to get in on the FREE BITCOIN!! by hosting a referral contest.
Crypto Tab is an extension that you add onto your Chrome or Firefox browser. Once installed, it taps into a Monero mining pool using your computers power and hash rate and mines coin on your behalf. For this, it pays you out in Bitcoin (BTC). I know, cool right?
The earnings are pretty slow if you're not using your browser all the time, or just keeping it open OR--- if you don't have a lot of referrals. Getting people aboard really makes a difference in how quickly you accumulate BTC. Just ask 
So to further incentivise the referral game, they are having a really groovy referral contest. The person with the most referrals by June 1 will win a whopping 0.3BTC There are prizes for second and third too as well as random prizes to be given out.
So Join!!!!
https://getcryptotab.com/231921
Use my referral code.... and then use YOUR code to refer all of your friends. A great way to make some money!!! Free Bitcoin!!