1. The folk dancing scene at Bilbo's party replaced by a most amusing break dancing sequence, featuring a digitized Sam and Frodo and a rock band made up of Elves, Orcs and Tree herders.
2. Golem jumps into the lava in a selfless attempt to save the others. He screams as he falls.
3. Add more tree herders to to thos scenes in The Two Towers. Add some humourous CGI such as a big tree knocking a little tree on the head, or maybe kicking him into the air. Hilarious!
4. New scene added at the end of ROTK, showing the orcs celebrating the demise of Sauronin the previously unseen Kingdom of Orcs. Oooh pretty!
Any other ideas?