https://www.techdirt.com/articles/20180212/12025739211/salon-offers-to-remove-ads-if-visitors-help-mine-cryptocurrency.shtml

As we've been discussing, the rise of stealth cryptocurrency miners embedded on websites has become a notable problem. In some instances, websites are being hacked and embedded with stealth cryptocurrency miners that quickly gobble up visitors' CPU cycles without their knowledge. That's what happened to Showtime recently when two different domains were found to be utilizing the Coinhive miner to hijack visitor broswers without users being informed. Recent reports indicate that thousands of government websites have also been hijacked and repurposed in this fashion via malware.

But numerous websites are also now exploring such miners voluntarily as an alternative revenue stream. One major problem however: many aren't telling site visitors this is even happening. And since some implementations of such miners can hijack massive amounts of CPU processing power while sipping a non-insubstantial amount of electricity, that's a problem.