Pugs's PIL2JS is nice, and Scheme2JS is rather complete with regards to R5RS, and now Ruby2JS.
Once all the JS-targetting people sit down and encode their calling conventions on top of the JS2 convention, and resolve inter-language calls between Ruby and Perl6 and Scheme, then it will serve the same niche as Parrot. And I think it will happen... maybe around Christmas. :-)
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