writes "Tom's Hardware Guide has an article up entitled 'Unwieldy Laptops or Portable Desktops?' in which the author lugs an Alienware Area-51m desktop replacement to a 32 hour LAN to assess what advantages and disadvantages desktop replacements have over desktops themselves."
They also have a related article entitled The Case of the 11 Pound Pencil
where an office adopts a desktop replacement solution to unsatisfactory ends. Both interesting looks at appropriate uses for hefty hardware.