As a general technology, I'm tentatively pro depending on how it is implemented. Torrent Freak makes some estimates its profitability, and it looks quite good.
https://torrentfreak.com/how-much-money ... ntfreak%29How Much Money Can Pirate Bay Make From a Cryptocoin Miner?
In a surprise move, The Pirate Bay decided to add a cryptocurrency miner to its website last weekend. The notorious torrent site wanted to see whether this could replace the ads on the site. A controversial idea, but how much money can a site like The Pirate Bay make through mining?
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The miner is provided by Coinhive which, at the time of writing, pays out 0.00015 XMR per 1M hashes. So how much can The Pirate Bay make from this?
To get a rough idea we did some back-of-the-envelope calculations, starting with the site’s visitor numbers.
SimilarWeb estimates that The Pirate Bay has roughly 315 million visits per month. On average, users spend five minutes on the site per “visit”. While we have reason to believe that this underestimates the site’s popularity, we’ll use it as an illustration.
We spoke to Coinhive and they estimate that a user with a mid-range laptop would have a hashrate of 30 h/s.
In Pirate Bay’s case this would translate to 30 hashes * 300 seconds * 315M visits = 2,835,000M hashes per month. If the miner is throttled at 30% this would drop to 850,000M hashes.
If Coinhive pays out 0.00015 XMR per million hashes, TPB would get 127.5 XMR per month, which is roughly $12,000 at the moment. Since the miner doesn’t appear on all pages and because some may actively block it, this number will drop a bit further.
Keep in mind that this is just an illustration using several estimated variables which may vary greatly over time. Still, it gives a broad idea of the potential.