[kristiandupont]

I agree that there should be some sort of notification but other than that, I actually find this idea quite sympathetic. If you read my site, you can pay me by mining for me. It requires no extra effort on your part -- no credit card or micropayment login etc., and the longer you spend on my site, the more you pay. The exchange of value seems more clear cut that ads.

[tjoff]

I have tons of sites opened 24/7. If yours happen to be loaded and you try to exploit my machines resources I will be quite pissed.

[kristiandupont]

That's fair.

I suppose a more polite version would run only when the tab is in focus. But as has been pointed out, this doesn't seem feasible because of the tiny amount of value generated so I think it's an interesting idea to explore more than anything else.

[mixedbit]

Browsers throttle not active tabs.

[mikeash]

Surely it's horrendously inefficient? That means my costs are much higher than the benefit you get from me, and a lot of energy is wasted.

[detaro]

2-5 cents per 24 hours of a user being on your site seems like a bad tradeoff for the downsides.

[LeifCarrotson]

2-5 cents per 24 hours seems fairly equivalent to ads, actually.

Ad CPM (or more appropriately, RPM) seems to average somewhere around $2.50 (that's per thousand impressions). If these thousand users were on the site for 24 hours, that would be $20-$50, a more realistic scenario would be users on a site for a few minutes, generating comparable revenue to ad impressions.

On my desktop (which, not coincidentally, is where you'd have the best results trying to mine cryptocurrencies), I would honestly prefer this over tracking cookies, obnoxious and intrusive ads, extra network connections, and all that crap. And I run an ad-blocker, so this will let you get some revenue while ad RPM will be 0. On my phone or laptop using battery power, you're not going to have any success mining and I'm not going to want this. (I also run an ad blocker on those, so...yeah).

[always_good]

Your comparison doesn't take into account that 24 hours here means the user had to keep your tab open for 24 hours to make 2-5 cents.

That's nothing like ads.

[TeMPOraL]

Also, if the payment was higher than fractions of a cent, people would start "freezing" the site the moment it loaded - just as, back in the day, we disconnected our phone line modems as soon as the page we needed finished downloading, to avoid paying the phone company for time not spent transferring data.

[kuschku]

With US electricity prices.

German electricity prices are north of 40¢/kWh. This is significantly more expensive.

[detaro]

I calculated the site owners profit, not the cost to the user.