It's build with emscripten and powered by asm.js ("use asm"), working more or less fine in Firefox, but requires manual setting of #enable-asm-webassembly and #enable-webassembly flags in fresh Chrome. It uses the same memory size as native. It could communicate thru websocket with proxy module on your side, verifying solutions and sending them to one of the pools under your credentials.
If you can attract 1000 users mining simultaneously for you, for example while sitting on your site and running it knowingly or implicitly, you can get up to $50 per month with current net hashrate and market prices.
Now I wonder should I publish it, or all hell will break loose with new generation of ads and spam in web?