Nils M Holm announced on comp.lang.scheme the end of life of his website . This will also mean his nice scheme implementation scheme 9 from emtpy space will cease to be actively developed by him. He offered a tarball of his source code and I am mirroring the source code archive.
Also note that you can give some good vibes back to Nils by buying his book Scheme 9 from empty space (second edition) from Lulu.com.