Cryptocurrency-mining in the browser (e.g. coin-hive.com) is one of the most interesting new models. Before you have an allergic reaction to this idea, let's first have a discussion of the best-case scenario.
Assuming that the publisher openly states they're mining instead of showing ads, and the user understands what's happening, browser-based mining is an attractive alternative to ads.
The first benefit is in privacy: you don't need to track your users personal preferences or identities. The second benefit is that there's no signup, no login, and no fraud.
It does not wholly solve the issue of attention-based revenue. That is, there is still some incentive for publishers to "manipulate" the user into long session times on the site. However, unlike ads, long session time doesn't have to mean long attention time in order for mining to happen.
Browser-based mining is sort of like micropayments: the user is paying the site in electricity. Many people don't want to pay subscriptions and they don't want to see ads. Browser-based mining is a viable alternative.