Actually, asm.js is JavaScript. That is, in fact, much of the point. It's kind of like the PyPy project's RPython: a restricted subset of Python that lends itself well to ahead-of-time compilation and optimization.

This leads to the question of whether (when?) someone will try to port Narcissus to it, potentially leading to a practical self-hosted JavaScript engine. "MonkeyMonkey", they could call it.