In an interview in Playboy's November issue, Colbert, a self-proclaimed Tolkien fan since childhood, hinted he might be heading for Middle-earth.
"Peter Jackson invited me to the set last year," he told the mag of his visit to the New Zealand set.
"I flew out and watched them shoot some scenes and went to some locations. I saw a 25-minute cut, and it was amazing. Jackson knows I'm a big fan of the films."
Asked by the interviewer if he would be making a cameo, Colbert smiled and said: "Could be."
'IT'S YET TO BE CONFIRMED OR DENIED'
Hobbit helmer Jackson has since been asked to address the Colbert casting rumours - and he's giving nothing away.
"I read that, too - it was very, very interesting," he told Entertainment Weekly. "It's yet to be confirmed or denied."
Jackson said of Colbert: "I have never met a bigger Tolkien geek in my life. Philippa Boyens is our resident Tolkien expert, and when Stephen came down to visit the set, we put him head to head with Philippa on a Tolkien quiz - and Stephen triumphed."
He jokingly added: "I have to say, his encyclopedic knowledge of Tolkien is spectacular, and points to a deprived childhood in some respects."
Check out the second trailer for The Hobbit: An Unexpected Journey here.
FAST GOSSIP
And finally...
* Britney Spears fans wig out over mag's cover photo, mag tweets apology: "Thank you all for sharing your thoughts on our cover! As always, we will share with our team and we're sorry to have let some of you down."
* Drew Barrymore and Will Kopelman make first public appearance since becoming parents, share baby snaps with Jennifer Aniston and Justin Theroux.
* Who says music and politics don't mix. "I don't care who you vote for as long as you vote for Obama" - Madonna booed by fans after she urges they vote for Barack Obama.
* Next chapter of the dream for Susan Boyle: Her rise to fame is being made into a biopic, and she wants Julie Walters to take the lead role.
* Today's riddle, courtesy of the Daily Mail: "Are Ashton Kutcher and Mila Kunis set to become Two And A Half?" Translation: Is she *sharp intake of breath* preggers? Read the official word here.
* "She certainly didn't break the group up, the group was breaking up" - Paul McCartney talks Beatles split, doesn't blame Yoko Ono.
* A very much not-engaged Kim Kardashian makes a splash dressed as a mermaid for NYC Halloween bash.
* Don't believe the type: Ke$ha very much alive as 'RIP Kesha' trends on Twitter.
* Just mates: Nicole Scherzinger rubbishes Chris Brown romance claims.
* "We're already working on different images" - Tom Cruise reveals plans for Mission: Impossible 5.
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- Rumour Has It