Chez Scheme price schedule I received in 2002:

    Chez Scheme Version 6
    Software License Fee Schedule
    V60901f
    
    Supported machine types:
       Intel 80x86 Linux 2.x
       Intel 80x86 Windows 95/98/ME/NT/2000
       Silicon Graphics IRIX 6.x
       Sun Sparc Solaris 2.x
    
    
    Classification                                  License fee (USD)
    -----------------------------------------------------------------
    Single Machines
      first machine per machine type                            $4000
      each additional machine                                    3000
    -----------------------------------------------------------------
    Site
      first machine type                                         9000
      two machine types                                         14000
      three or more machine types                               19000
    -----------------------------------------------------------------
    Academic Site (for qualified academic institutions)
      first machine type                                         4500
      two machine types                                          7000
      three or more machine types                                9500
    -----------------------------------------------------------------
    Corporate
      each machine type                                         24500