Alan Lee (a Tolkien artist and conceptual designer with John Howe) has a cameo as one of the nine men who received a ring of power in the Prologue.

Ian Holm, who plays Bilbo Baggins, was the voice of Frodo Baggins in a radio play version of "Lord of the Rings."

Sean Bean (Boromir) was deathly afraid of riding in the helicopter that had to take the actors to and from the many filming locations. After the scene on Caradharas, the one where Boromir tries to take the ring from Frodo, Bean refused to go anywhere else by helicopter. Many times he had to take a ski lift and climb many hundred feet in full Boromir gear to get to the set.

Elijah Wood (Frodo) filmed his audition out of the casting office. He memorized the script there (he wasn't allowed to remove it), bought a Hobbit-ish costume, and had a friend of his film his audition in the Hollywood Hills. Jackson chose him because he looked like what a Hobbit should look like - in a costume with no shoes, sitting on the side of a hill, giving lines like he should be giving them.

When Frodo falls over in the snow and loses the Ring, there's a close-up of the Ring, with Frodo in the background. A giant ring of six inches in diameter had to be used to keep both Frodo and the Ring in focus.

Christopher Lee (Saruman) reads "The Lord of the Rings" once a year, and is the only cast member to have actually met J.R.R. Tolkien.

John Rhys-Davies (Gimli) is actually the tallest member of the Fellowship (Christopher Lee's the tallest member of the cast).

During the scene before Bilbo's party, when Gandalf and Bilbo are inside Bag End, Gandalf hits his head on a beam upon entering Bilbo's study. This was actually unintentional, but Ian McKellen did such a good job of acting through it that Peter Jackson left it in the movie.

During a fight scene with the Orcs, Viggo Mortensen (Aragorn) got hit in the mouth with a sword and it broke a tooth. He tried to convince the crew to put it back with superglue, but for obvious reasons Peter Jackson didn't let him. He went to the dentist that afternoon to get it fixed.

In the scene where Frodo and Sam are leaving the Shire and walk through a cornfield, you may notice (a very subtle touch by the filmmakers) that the Scarecrow is covered in crows. Seems it wasn't doing a very good job.

In the scene near the end when the Fellowship is canoeing down the river, Legolas and Gimli's boat capsized because of a crew member trying to prevent them from floating downstream. Gimli started to sink because of the chain mail, and rescue boats came swarming out to save them.

When Frodo is leafing through Bilbo's Book in Rivendell, a page with dwarven runes is shown. The runes translate thus: "Stand by the grey stone when the thrush knocks, and the setting sun with the last light of Durin's Day will shine upon the keyhole." This is a reference to the map in "The Hobbit" and the runes tell of the secret entrance into The Lonely Mountain.

Extended version - At the party, Bilbo hides from Lobellia Sackville-Baggins. Look closely and you may recognize the actress as Lionel's zombie mother from Peter Jackson's film "Brain Dead"/"Dead Alive."

In the scene right after Bilbo leaves, Gandalf is sitting by the fire thinking to himself about how Bilbo acted when asked to give the ring to Frodo, calling it his "precious" and all. While Gandalf is thinking, he mutters, "Riddles in the Dark." "Riddles in the Dark" is actually the name of the chapter in "The Hobbit" where Bilbo finds the ring.

Arwen and Aragorn are actually related. Arwen's father, Elrond and his brother Elros were half-elven. They were given a choice of whether they would like to become elves and become immortal; or be mortal and become the kings of Men. Elrond chose the elf option, and his brother the mortal one. Elrond had Arwen, while his brother's family tree went on for thousands of years, eventually resulting in Aragorn making Arwen Aragorn's first cousin many-times removed.

I really liked the subtlety of this and thought I'd share it - there's a part in the book, 'The Fellowship of the Ring', just after Frodo has been grabbed by the Watcher in the water outside the gates of Moria. Gandalf thinks, but does not say, that 'whatever it was that dwelt in the lake, it had seized on Frodo first among all the Company' ie. the implication being that the ring draws attack and evil from all around. This happens in the film too - the first Ringwraith is able to separate Frodo from the other three hobbits, when they're running for the Bucklebury Ferry, the Watcher grabs him, as in the book, and even the Cave Troll singles him out. Submitted by STP

Not a mistake, but a wonderful in-joke. When Boromir is teaching Merry and Pippin to use their swords, you can hear him counting numbers as he delivers the blows to be parried. These numbers - "2, 1, 5" - are in fact the correct numbers for the system of parries used by the Society of American Fight Directors, and many stunt coordinators and fight masters worldwide. Boromir even matches the numbers to the correct locations. The numbering system is supposed to have been based on historic European fencing manuals, but if the folk of Middle-Earth knew it, it must have be a good deal older!

When the four Hobbits fall down the hill, Merry says "That was just a detour, a shortcut." Sam asks "A shortcut to what?" and Pippin says "Mushrooms!" This is a reference to a chapter in The Fellowship of the Ring called "A Shortcut to Mushrooms." A number of chapters are referred to within the dialogue in various places. Others include: "A Long-expected Party," "At the Sign of the Prancing Pony," "A Journey in the Dark" and "The Breaking of the Fellowship." All of those chapter names except "A Shortcut to Mushrooms" and "A Long-expected Party" were also used by composer Howard Shore to name a piece on the LOTR soundtrack.

A pictorial cameo: The two portraits in oval frames hanging above the fireplace in Bag End are of Peter Jackson and Fran Walsh.

After being cast as Peregrin Took, Billy Boyd was advised by Peter Jackson to tone down his Scottish accent because it stood out from the other hobbits' English accents, so during rehearsals he used a Gloucestershire accent. However, PJ and crew decided that Pippin's lines sounded funnier in his normal accent, so he returned to it.