Stand up halfway through the movie and yell loudly, "Wait...where the hell is Harry Potter?"
Block the entrance to the theatre while screaming, "YOU.....SHALL....NOT..... PASS!"
Play a drinking game where you have to take a sip every time someone says, "the Ring."
Point and laugh whenever someone dies.
Ask everyone around you if they think Gandalf went to Hogwarts.
Finish off every one of Elrond's lines with "Mis..ter Ander-sonnn."
When Aragorn is crowned king, stand up and at the top of your lungs sing, "And I did it.... MY way...!"
Talk like Gollum all through the movie. At the end, bite off someone's finger and fall down the stairs.
Dress up as old ladies and re-enact "The Battle of Helms Deep," Monty Python style.
When Denethor lights the fire, shout "Barbecue!"
In TTT when the Ents decide to march to war, stand up and shout, "RUN FOREST, RUN!"
Every time someone kills an Orc, yell: "That's what I'm Tolkien about!" See how long it takes before you get kicked out of the theatre.
During a wide shot of a battle, inquire, "Where's Waldo?"
Talk loudly about how you heard that there is a single frame of a nude Elf hidden somewhere in the movie.
Start an Orc sing-a-long.
Come to the premiere dressed as Frankenfurter and wander around looking terribly confused.
When they go in the paths of the dead, wait for a tense moment and shout, "I see dead people!"
Imitate what you think a conversation between Gollum, Dobby and Yoda would be like.
Release a jar of daddy-long-legs into the theatre during the Shelob scene.
Wonder out loud if Aragorn is going to run for governor of California.
When Shelob comes on, exclaim, "Man! Charlotte's really let herself go!"
After the movie, say "Lucas could have done it better."