anchor.diff:      tetex
       texinfo
       thunderbird
  +    tightvnc
       transformers
       uml
       unzip
  
positive.code:     bmp_plugin_musepack
      bsdiff
      bzip2
      cksfv
      coreutils
      darcs
  
negative.code:     mktemp
      mono
      mysql
      nix
      nxml
  #    octave
      openssl
  