Expected a "10 things you already know" list, but ended up quite surprised by some of these.

I found the last two especially interesting.

Why not mentioning running Linux kernel? http://bellard.org/jslinux

Also, with https://github.com/kripken/emscripten you can run a "port" quite a bunch of apps to JavaScript.

And don't forget you can decode several audio codecs: http://labs.official.fm/codecs/ and video codecs: https://github.com/mbebenita/Broadway + http://people.xiph.org/~bens/route9/route9.html

None of these are massively surprising, you can pretty much shim your way into doing anything when you have control of the environment. Turing equivalence and all that..