Harvest - Distributed Browser Blockchain (Monero)
It's possible to mine Monero in the Browser, relatively efficiently, using ASM.js and/or WebAssembly. The performance of Mining in the browser doesn't match native C++ currently. In the future, Browser Virtual Machines will match or come close to native compiled byte-code.
Fast forward to present day and smart people have realized "ohhh" we can build CPU Miners in the browser now.