Javascript unauthorized use of cpu

Accidently I found a site that through the use of javascripts, it leeches my cpu and it won't stop until the pc is restarted. I don't know if it's considered malware or something like that but I don't think that leeching cpu power without authorization is a good thing. This is the page that I was browsing when the cpu started running for no reason, I didn't install or click anything, just browsing the site (I used paint to write the link because I don't want to cause troubles to anyone):


Something like this might generate a huge botnet, I think.. but I'm not an expert, so if you think that there's no risk then you can remove this post, sorry.

:thanks:

Not positive

I am not sure on this but,you are correct in the sense that this is a bot net. Bitcoin miners make money form clicking adds, it is like the Yontoo virus http://www.scmagazine.com/yontoo-adware-used-to-cash-in-on-clicks-targets-mac-and-windows-users/article/285506/

This is a similar case:
http://kotaku.com/e-sports-league-mined-bitcoins-with-subscribers-comput-486205191

Even though they used the GPU instead and the infection method was different, it's a very similar case of botnet. I don't mind mining if it's for me (100% supporting the free currency concept) but I don't like when someone abuses my hardware to make profit, because it's so frustrating when my pc is slow and can't use anything.