While the DC Comics Universe sets itself outside of reality by using fictional cities like Metropolis and Gotham, Marvel Comics likes to have their superheroes, for the most part, to feel like they are living in the world as the readers, but just slightly removed from reality.

RELATED: 10 Comic Books You Didn't Know Were Written By Celebrities

And along with using very real places like New York City as the hometown for many of their superheroes, Marvel also likes to drop real people into their comics from time to time, with special attention to celebrities who may be able to grab a headline or two along the way. While some of these men and women may not be as famous as Deadpool is these days, they are all very real.

10 David Letterman Interviewed The Avengers

David Letterman and the Avengers Marvel Comics

One of the greatest late-night hosts in television history, David Letterman was known for being the coolest guy on TV after 11 pm, and part of being cool was his ability to hang out with superheroes. In Avengers #239 by Roger Stern & Al Milgrom, Wonder Man convinces Vision and some former members of the team to go on Letterman's show in order to help his burgeoning acting career. While the heroes are on TV, their old enemy Fabian Stankiewicz attacks them, and he may have won the day if not for David Letterman's quick thinking.

9 Spider-Man Teamed Up With The Original Saturday Night Live Cast

John Belushi Spider-Man Marvel Comics

While Marvel Team-Up was known for having Spider-Man come together with other heroes in the Marvel Universe, Chris Claremont & Bob Hall's issue #174 saw the web-slinger working alongside the Not Yet Ready for Prime-Time Players.

RELATED: 10 Comic Book Ads That Feature A Celebrity

When John Belushi finds himself in possession of a strange ring, he and the rest of the original cast of Saturday Night Live find themselves being attacked by the Silver Samurai on live TV. Luckily, Peter Parker and Mary Jane just happen to be in the audience, and Spider-Man is able to swing in and save the day.

8 Shannon Elizabeth Went To Space With Tony Stark (Ultimates)

American Pie actress Shannon Elizabeth in Marvel's Ultimates

With the Ultimate Universe, Marvel looked to reboot and reinvent their characters for the 21st century, and in the case of The Ultimates, that included a lot of then-current pop culture references. And while the Hulk's hatred for Freddie Prinze Jr. is well known, what often gets overlooked is that in issue #3 of The Ultimates by Mark Millar & Bryan Hitch, Tony Stark is hanging out in space with Shannon Elizabeth, the actress best known for her role in American Pie. As explained by Tony during an interview with Larry King, Marvel's most famous billionaire took the famous actress on an out-of-this-world vacation for her birthday.

7 Stephen Colbert Was Almost The President In Marvel Comics

Stephen Colbert teamed up with Spider-Man

In 2007, the looming United States presidential election was just getting started as both the Republican and Democratic parties held their primaries. But in the Marvel Universe, Stephen Colbert - best known as the host of the Colbert Report on Comedy Central at the time - was running for the White House as a third-party candidate.

As seen in Amazing Spider-Man #573 by Mark Waid & Pat Olliffe, Colbert's presidential run wasn't going well, and after leaving a sparsely attended campaign rally, the TV host found himself caught in the middle of a fight between Spider-Man and Grizzly. Colbert offered to help Spidey, but the famous hero insisted the comedian stay out of the fight for his own safety.

6 Barack Obama Beat Stephen Colbert

Spider-Man and Barack Obama teamed up

While Barack Obama won both the popular vote and the Electoral College in the real world during his 2008 presidential run, in the Marvel Universe, the Senator from Illinois actually lost the popular vote to Stephen Colbert, but still won the Electoral College vote and became President of the United States.

RELATED: 10 Times Real People Appeared In Comic Books

It was during his Presidential Inauguration that the 44th President of the United States met Spider-Man after a second Barack Obama arrived at the swearing-in ceremony. Thanks to Spider-Man's quick thinking, it was soon revealed that one of the Obamas was actually the Chameleon in disguise.

5 Penn & Teller Teamed Up With Spider-Man & Deadpool

Penn and Teller Meet Spider-Man and Deadpool

Famous for their own special brand of magic and for digging deep into commonly held misconceptions, Penn & Teller have made a name for themselves for never doing things the easy way. In Spider-Man/Deadpool #11, the famous duo took things to a whole new level when Deadpool - also known as the Merc with the Mouth - and Teller - famous for never speaking - switched places.

In the story, written by Penn Jillette himself, Deadpool steps in for Teller during a Vegas show, which allows Penn to finally let loose with his nastiest ideas.

4 Jay Leno Drove Spider-Man Around Town

Jay Leno and Spider-Man by Greg Capullo

Jay Leno may have made more appearances in Marvel comics than just about any other real person. The one-time host of The Tonight Show has appeared in a number of Marvel titles over the years, starting with Amazing Spider-Man #332 by David Michelinie & Erik Larsen where Jay Leno is a special guest at a charity event that Spider-Man is also attending. Since then, Leno has shown up in Incredible Hulk, Iron Man, and even teamed up with Spider-Man in the three-part story "One Night Only! (Don't Forget to Tip Your Waitress)."

3 Jeremy Lin Hulked Out

Jeremy Lin and Amadeus Cho Marvel Comics

A former Brooklyn Nets point guard, Jeremy Lin became an overnight basketball sensation who soon found himself not only on the cover of Sports Illustrated but also teaming up with Amadeus Cho in Totally Awesome Hulk issues #13-14 by Greg Pak, Luke Ross, & Germán Peralta.

In the two-part story, Hulk and Lin must work together to stop QUASI/MO/DO from connecting all the world's robots into a hivemind that he controls. Luckily, basketball skills end up being pretty useful against robots, and Lin and Hulk are able to stop the villain's plan and save the day.

2 Uri Geller Lent His Mental Powers To Daredevil

Uri Geller and Daredevil working together comics

Sadly, superpowers don't exist in the real world, but illusionist Uri Geller is about as close as anyone has come to being a mutant straight out of the comics. Geller, who became famous for his supposed psychokinesis and telepathic abilities was so convincing that even the CIA and the Defense Intelligence Agency tested him and couldn't figure out how he pulled off his tricks.

RELATED: Real Heroes: 10 Great Comics Based On True Stories

Uri Geller got the chance to be a superhero when he showed up in Marv Wolfman & Bob Brown's Daredevil #133 where he teamed up with the Man Without Fear to stop the villainous Mind-Wave and put an end to a crime wave that was gripping New York.

1 Justin Trudeau Helped Alpha Flight Make A Decision

Canadian Prime Minister Justin Trudeau and Marvel's Alpha Flight in Marvel Comics

In the events of Civil War II, the heroes come across an Inhuman named Ulysses Cain who can see into the future. Captain Marvel believes that the Avengers should use Cain to stop crimes before they happen, but not all the heroes agree with that plan, and a debate over fate and free will begins.

In the story, the members of Alpha Flight speak to their boss, the 23rd Prime Minister of Canada Justin Trudeau, who feels that using Cain is a bad idea. What's really amazing is that Trudeau's father Pierre, the 15th Prime Minister of Canada, has also appeared in Marvel books, most notably in John Byrne & Chris Claremont's Uncanny X-Men #120 where he sends Vindicator to capture Wolverine and bring him back to Canada.

NEXT: 10 Times Real-Life Famous Figures Were Spotted In Anime