The problem with ads is that they are not just ads these days. There is a big industry whose "product" is tracking users across sites, trying to build detailed

The problem with ads is that they are not just ads these days. There is a big industry whose "product" is tracking users across sites, trying to build detailed profiles in order to present people with targeted ads they are more likely to click on. In other words, a massive invasion of privacy that may very well come back to haunt us (think of an oppressive government trying to find potential dissidents, either to bombard them with propaganda or worse). Using my browser as a cryptocurrency miner as I visit a site has obvious problems, especially on mobile devices, but from a privacy perspective it is far less troubling. With the exception of blogs people write in their spare time, most web sites need a way to recover their expenses. Even more so for news sites that employ journalists etc. At that point, the interesting question is how effective running a Javascript miner is. When I visit web sites using a browser that has no ad blocker or tracking protection installed, I notice that ads, tracking scripts, etc. can use quite a bit of CPU, RAM and bandwidth, too. If I could be sure that a site using crypto-miners does not just gobble up my phone's battery like crazy, the idea is not that bad, as long as sites are transparent and up-front about it. Some sites already offer a model where you either have ads or make a donation and get an ad-free page. Something similar with cryptominers could work, too. (All this assumes, of course, that web site owners play fair, which is hopelessly naive all too often.)