Now that full-system emulation has been shown to be feasible and performant in javascript, it's like the four minute mile has been broken and it will be interesting to see the hundreds of variations and practical uses of these techniques that will result.
But, if you really want to go there, based on the dates listed on http://www.tramm.li/iWiki/FrontPage.html, this was done a few months prior to Bellard's x86 emulator :)