Monero? Existing botnets earn $50,000/day mining on people's computers at night while finding ways to spread to additional ones.

A single computer earns pennies, a couple hundred thousand earn way more.

A single computer rarely even earns pennies.

It would be fun if AES-NI support was added to JavaScript engines, though it would need a standard.

As far as I'm aware, AES calculations aren't a component of any cryptocurrency.

Yes, Monero uses the CryptoNote PoW algorithm which uses AES.

A customer base of hundreds thousands doing streaming will cost you way more than $50k/day.

It doesn't have to completely cover the costs, only offset it some and be used in conjunction with other income generation methods.

Personally, I don't mind it so long as it is both fully disclosed and the ramifications fully explained - both in an accessible manner to a layperson. So long as they do that, I'm okay with it. I'm more okay with it if they give the user a simple means to opt out in a meaningful fashion.

Now, chances are exactly none of those conditions will be met in the real world. But, in principle, I am okay with it.

Unless you just package it and let youtube do the actual streaming. Imagine creating "cat-videos.com" and embedding all the youtube videos into the site but providing a better UI for browsing them.

But you'd get both ads and mining. The point of mining was to get rid of ads!