This is used by the Larceny Scheme compiler, which recently had a release:<p><a href="http://larcenists.org/download.html" rel="nofollow">http://larcenists.org/download.html</a><p>And it's apparently generating some pretty fast code:<p><a href="http://larcenists.org/benchmarksGenuineR7Linux.html" rel="nofollow">http://larcenists.org/benchmarksGenuineR7Linux.html</a>