The Storyteller

One of the oldest archetypes; a character that is noted for his or her ability to tell tales, or at least their propensity to do so.

Once upon a time...

Sometimes the tales have a purpose in the main plot. At other times it is simply an interesting side excursion, perhaps to give the setting a feeling of depth.

Sometimes overlaps with Miles Gloriosus and The Munchausen. Could conceivably be made to overlap with Intrepid Reporter.

For the Jim Henson series, see here.

Examples of The Storyteller include:

Anime and Manga

Jun Kudo from Sayonara, Zetsubou-sensei, especially a master of the Tear Jerker tales. Of course, we hardly ever get to hear any of his stories...

Comic Books

Kitty Pryde in the classic X Men issue "Kitty's Fairy Tale", made up a bedtime story for young Illyana Rasputin, casting herself as the heroine and other members of the X-Men as characters. Notably, Kitty cast Cyclops as a prince and Jean Grey as a princess cursed by the evil Phoenix, and gave the Scott and Jean in her story the Happy Ending their counterparts were denied.

Fairy Tales

In The Black Thief and the Knight of the Glen, the thief saves the lives of his companions by claiming to have been in more danger than they were, and the knight gives him their lives, one by one, to get the stories. The last story recounts how he saved the life of a baby, and the knight's old nursemaid assures him that it's true and he was the baby.
- Conal Yellowclaw has the same plot, though he is the father of the men he's saving.

Literature

Scheherazade in Arabian Nights.
Fflewddur Fflam in Prydain Chronicles, doing part-time as a Spoony Bard.
Dandelion in Watership Down (among the main group, he told most of the stories of "the prince of a thousand enemies".)
- Bluebell gets to tell one, as well. He's also telling a story to keep some of the other rabbits calm, during the climactic scene.
Bilbo in Lord of the Rings. Also Aragorn.
Brom in Eragon is widely regarded as one of the greatest storytellers known.
Puck in Puck of Pucks Hill by Rudyard Kipling.
- Also the two Intrepid Merchants in Ballad of the King's Jest by the same author.
Belgarath in The Belgariad has masqueraded as a traveling storyteller, and his storytelling abilities are genuinely good.
The Minstrel in The Last Hero, who is dragged along by the Silver Horde to chronicle their last great act of heroism. It is revealed at the end that he is only The Minstrel - no name other than that - and his entire purpose is to be the one that tells the tale. Despite his battered appearance by the end of it all, he seems to be a pretty good sport about the whole thing. Or else he has been driven insane by the ordeal and forgotten whatever name he had before.
Taleswapper (aka William Blake) from the Alvin Maker series
Chronicler from The Name of the Wind
Thom Merrilin in The Wheel of Time.
David Copperfield was this in his Boarding School of Horrors.
In Terry Brooks's Scions of Shannara, Par and Coll Ohmsford were acting as storytellers while trying to avoid capture.
The title character in L. M. Montgomery's The Story Girl.
Sara Crewe in A Little Princess, as well as all the adaptations thereof. Especially notable in the Alfonso Cuaron film and in the anime, where her narratives are shown in detail, and become an important plot point.
The title character of The Book Thief, by Marcus Zuzak, finds she can calm people down by reading aloud to them during an air raid in World War Two Dresden.
Marianne Engel in The Gargoyle.
The unnamed gentleman in the short story "The Storyteller" by H. H. Munro (better known as Saki).
Colas Breugnon, the narrator and protagonist of the novel of the same title.
In A Song of Ice and Fire Old Nan is both the children's caretaker and the storyteller of Winterfell. She's particularly fond of telling scary stories about the Others.
In Michael Flynn's The January Dancer, the harper sought out the scarred man to get him to tell her his stories, so she could write songs about them.
Poul Anderson's version of Hrolf Krakki's Saga is put in the mouth of a woman visiting the court of Athelstane of England with some tales from the Baltic.

Film

Dilios, in Three Hundred, though according to the film's director Zack Snyder, he "knows how not to wreck a good story with truth."
Ed Bloom, in Big Fish.
Uncle Garth, in Secondhand Lions.
Wendy, to a degree, in all adaptations of Peter Pan, but especially in the 2003 film.
The Grandfather character in The Princess Bride.
C-3PO, relating the heroes' story to the Ewoks in Return of the Jedi, which actually justifies his presence in The Empire Strikes Back and Jedi's prologue: He had to witness the story to tell it later.

Live Action TV

Buffy the Vampire Slayer: Andrew, starting in Season 7, with him endeavoring to educate the Slayer Potentials. Played for Laughs due to him being a bit of a Cloudcuckoolander at best and suffering the occasional Critical Research Failure in regards to the show's continuity.
Numb3rs : Interestingly enough Charlie Eppes, who constructs entertaining parables to illustrate math.
Gabrielle in Xena The Warrior Princess was a fantastic flair for storytelling before she became a full-fledged Action Girl and even taught Homer a thing or two.
The afore-mentioned short-lived Jim Henson series The Storyteller (unsurprisingly) featured one. He was credited just as "The storyteller" and his storytelling was the Framing Device for each episode. He was also the protagonist of one story.
Stella from Barney and Friends.

Religion and Mythology

Older Than Feudalism: In The Bible, Jesus was known for illustrating religious points with parables.
The Talmud has also has several examples.
In Norse Mythology, Odin has charge over riddles and poetry and runes and the like.
Anansi the Spider, who even challenged the gods (or Tiger, depending on the version you're reading), so that he would be considered king of all stories.

Theatre

In the Backstory of Othello, this is how Othello won Desdemona.

Her father loved me, oft invited me,
Still questioned me the story of my life
From year to year, the battles, sieges, fortunes,
That I have passed.
I ran it through, even from my boyish days,
To th' very moment that he bade me tell it,
Wherein I spoke of most disastrous chances,
Of moving accidents by flood and field,
Of hair-breadth ’scapes i' th' imminent deadly breach,
Of being taken by the insolent foe
And sold to slavery, of my redemption thence
And portance in my traveler’s history.

Wendy in Peter Pan. The fact that she knows "lots of stories" is what makes Peter take her to Never Land in the first place, since the Lost Boys don't know any stories. In early drafts of the script, even the Indians listen in.

Web Comics

Theopholous Dumedd of Girl Genius.
Koark from Order of Tales. The eponymous Order is devoted to telling and preserving tales; Koark is the last of their kind.
Fuschia in Sinfest. When she leaves Hell, the damned notice that storytime is come and no story has.

Video Games

Manari from the Samurai Shodown Spin-Off Nakoruru: Ano Kara no Okurimono. She's actually from a whole clan of these.
Homeros in Fire Emblem Jugdral's Thracia 776.
Vernon from Psychonauts is an limitless warehouse of incredibly long and boring stories.

Western Animation

From Disney Fairies: Spinner in the books and Lyria in the movies are Story-Teller talent fairies.
Gerald from Hey Arnold! tells a lot of Urban Legends.
Cherilee in the third generation of My Little Pony. The intro even spells it out for us: "I hope we hear a story from Cherilee!"
This is Butch's entire shtick in Recess
An episode of the X Men animated series puts Jubilee in this role. When she and a bunch of non-powered children are trapped in a cave, she cheers them up via telling them stories where she cast herself as an Action Girl, Gambit and Wolverine were her teammates, Professor Xavier was The Mentor...

Real Life

Scottish Clans will often have an official clan bard. In times passed this could be hereditary or perhaps a close relation of the chief. They would follow close behind the chief in battle to make sure the clan's glorious deeds were recorded. The clan's inglorious deeds were of course treated differently.