Okay, this is out of the book, I'll have to check my DVD for any differences in the movie later.
Player: "A Balrog, Now I understand what the DM is up to. What an Evil encounter! And I am already out of high-level spells."
DM: " The dark figure steaming with fire races towards you. The Orc yell and pour over the stone gangways behind it.
Other Player: "I blow the Horn of Gondor!"
Others laugh in a juvenile mood.
Third Player: "That always cracks me up."
DM: "Um... the Orcs stop dead in their tracks, awed by the challenge, but the Balrog pushes on undaunted, giving them greater strenght of will. They continue."
Player: "I summon all the strenght I have left and shout 'Over the bridge! Get the Hell out!' This is a Challenge Rating beyond any of you."
Yet Another Player: "Well, I'm outta here!"
Other Player: "I'm not leaving Ol' Gan to fight this demon-thingy alone! He's way ahead of us on Exp. and levels already!"
Player the Fifth: "He's right! And with me being his best friend and future king and all I should help!"
DM: "As the Balrog reaches the bridge, your Holy Avenger gleams cold and white. It halts before you, spreading it's wings casting a vast shadow on the walls behind it."
Elf Player: "A Wizard with a Holy Avenger?! And you complain about my 'broken' Archery progression!"
Player #1: "'You cannot pass!' Does it frighten them?"
DM: "The Orcs stop and grow eerily quiet. But the Balrog seems unimpressed."
Player: "'I am a servant of the Secret Fire, and wielder of a Ring of Elemental Command (Fire)! You cannot pass! The dark fire will not avail you, flame of Hell!'"
DM: "Udun. My campaign's hell is called Udun."
Player: "Okay, 'the dark fire will not avail you, flame of Udun! Crawl back into the Underdark. You cannot pass!'"
Back-Up Hobbit Player: "Niiiice!!"
DM: "The Balrog makes no answer. It grows darker, and stabs at you with it's flaming sword." (rolledy-roll) "Miss. What do you do?"
Player #1: "Can I disarm or sunder his sword with Glamdring?"
DM: "You can try! Make an attack roll."
Player: (Rolls) "W00t! Natural Twenty!"
DM: (groans) "Not again! Okay, there's a flash and a metallic sound, and the Balrog's sword falls away in molten pieces."
Player: "I repeat: 'You cannot pass!'"
DM: "The Balrog leaps forward at your challenge, brandishing its many-thonged whip."
Player the Fifth: "He can't take it on alone! I run up and help him!"
Other Player: "'For Gondor!' I follow Aarg!"
Player: "Get back, idiots! I cast my last Maximised Fireball at the Balrog's feet!"
All others: "What?! Are you insane!"
Player: "I can take the damage! And in the campaign notes it said that the Bridge of Khazad-Dum is thin and narrow, so if I break it while the Balrog is on it..."
DM: "...."
Player: "Well?"
DM: "I.. I... Okay! Okay! The bridge cracks, and the Balrog plummets to his death! But even as it falls, it swings its whip, tripping you per the whip rules combined with Improved Trip. You stagger and are dragged off. Any last words?"
Player: "... Why you..."
DM: "To the Fellowship, I mean!"
Player #1: "
Expeditious Retreat, you fools!"

that was fun