Enscript is such a versatile and helpful tool.
Here is how I use it to pretty print Scheme code:
enscript --landscape --columns=2 --highlight=scheme --borders --line-numbers --output=.ps .ss
Addendum: 03/06/09
Here is the direct link for the GnuWin32 download of Enscript.
Addendum: 03/08/09
Here are my new favorite settings for rendering code with this excellent program:
enscript --word-wrap --underlay=Underlay --ul-gray=0.9 --line-numbers -- landscape --highlight=scheme --columns=2 --borders --output=test.ps C:\collects\wisdomandwonder\resume\latex-renderer.sls