Dokludi has replicated this truck attachment to selfload/unload containers:
"The Combilift containerlifter is able to transport all sizes of ISO shipping containers. The Containerlifter hooks on behind a normal Truck and can lift fully loaded containers from the ground onto the trailer, from trailer to trailer and from trailer to ground."
For understand properly how it works you must see the video:
And the real thing in action:
Amazing device and reproduction, for more details visit the brickshelf galery.