digraph G {
  /* OS to binary vs source */
  linux -> linux_source;
  linux -> linux_binaries;
  windows -> windows_binaries;
  irix -> irix_source;  
  irix -> irix_binaries;
  irix -> irix_source;  
  /* Binaries */
  linux_binaries -> { "RH 7.3"; "Fedora 3"; "SuSE 9.0"; }
  windows_binaries -> { "98"; "2000"; "NT"; "XP"; }
}