I don't know about WIZnet, but I've heard that TI are doing it for the CC3100 (or whatever it's called)
@Gordon started
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
I don't know about WIZnet, but I've heard that TI are doing it for the CC3100 (or whatever it's called)