The idea to use bitcoin mining in place of ad revenue has been tried before (unfortunately the state of New Jersey didn't like it): https://venturebeat.com/2014/02/12/new-jersey-slaps-mit-bitc...

Actually New Jersey changed their mind. They didn't follow up with their investigation and concluded "we do not believe Tidbit was created for the purpose of invading privacy." https://www.eff.org/cases/rubin-v-new-jersey-tidbit

This discussion comes up every once in awhile. It's horribly inefficient.

Six years ago:

https://news.ycombinator.com/item?id=2566365

Additionally, does this automatically hook in to slush's pool or something? Bitcoin mining is practically useless on CPU; even the fastest CPUs out get way, way less than 10mhash. The average length of time to find a block at 9999khash and current difficulty is 1200+ days, so even that estimate is over-optimistic, so this isn't worth anything if your users don't sit on your site for 5 years+, unless it's hooked into a pool or some other contraption to pay on shares instead of blocks.

It hasn't gotten better.

This isn't bitcoin. The mining is completely different.

You're right.

Monero is different. To mine Monero, you have to calculate hashes with an algorithm called Cryptonight. This algorithm is very compute heavy and – while overall pretty slow – was designed to run well on consumer CPUs.

There are solutions to run the Cryptonight algorithm on a GPU instead, but the benefit is about 2x, not 10000x like for other algorithms used by Bitcoin or Ethereum. This makes Cryptonight a nice target for JavaScript and the Browser.

Would it be more efficient using Web Assembly ?

Just saw it, coin-hive use Web Assembly already :

Our miner uses WebAssembly and runs with about 65% of the performance of a native Miner.

IDK man, YouTube tries to force people into their inefficient video format, burning way more power because they refuse to pay for x264 licensing.

No on both fronts.

Youtube does transcode to H.264 (which is the format which requires licensing, x264 is an open source encoder that outputs H.264 encoded video). There are a variety of chrome extensions and similar which will allow you to select H.264 on the majority of Youtube videos if you so choose, much of youtube's content is available in h264 as well as other formats.

Second, the reason that they default to VP9 is because it is a better low-bandwidth experience. It's certainly a tradeoff against power usage with H.264 since hardware acceleration for H.264 decoding is often available, but it is a calculated tradeoff based on the fact that people want their videos to load faster and in higher quality. You can read a little bit more about that here. https://youtube-eng.googleblog.com/2015/04/vp9-faster-better...

Yeah forgot to mention it's 4K h264 thats not available anymore. And they do still force VP8/9 on you, regardless of your network or hardware.

p.s. did checked coin-hive.com and hash rate is really poor - 24h/s on a 4 core machine is truly nothing compared to modern hardware miners.

We are talking about Monero. Also, give it time to ramp up. I get more h/s on my iPhone.

Newer graphic chips also have VP.9 hardware decoding support. Even Intel's integrated graphics and smartphone SoCs support it. It just needs to catch on, like H.264 hardware decoding had to.

What makes you think it's illegal?

Some MIT students were harassed by the government when they built the idea at a hackathon a few years back.

Could you provide a link? I wasn't able to find anything.

I would consider this evidence of massive overreach on the part of law enforcement rather than evidence that it's illegal (which afaict it still is not).

Yeah, I wonder if I can run this on some apps. Just tell people up front - this app mines crypto, pay $1 to shut it off.

What if google or facebook would have this on their embed code?!

Seeing as how slow Facebook app is, they are probably mining both Bitcoin and Ethereum

They'd mine a few tons more by using native miners on their own servers instead of javascript on all the clients.

Then they'd have to pay for the electricity.

I can still imagine it. The team that mines Bitcoins to pay for their social event would probably not be part of the division that pays the electricity bills.

They probably don't, but how can you be sure without auditing each and every js embed that you download?

with the state of js these days... everything is possible

If this included they kind of code in a big % of websites, wouldn't this make the difficulty of getting new blocks so high that it would become an inefficient way of mining?