Have you heard of CryptoTab Browser?
I'm pretty happy with it. I'm able to surf the internet and mine bitcoin at the same time. It’s a pretty simple, straightforward really: you get a personal referral link and invite people to download CryptoTab Browser. Those who followed the link and started using the browser will become members of your network: you’ll receive a percentage of cryptocurrency they mine. Moreover, it’s not only them who will bring you income: every user, who was brought by your referrals, will be accounted as your network participant. Members on the second, third and subsequent levels will bring less income — but they will be much more. In total, your mining network can consist of up to 10 levels.