SANTA MONICA, California -- According to reports, Vince Vaughn was paid $20 million to star in "Fred Claus." It goes to figure, then, that the man's time is extremely valuable, and that he could earn eight figures anytime he feels like blocking off a month or two for filming. So, what the hell was he doing in the back of a tour bus, crammed in with a bunch of middle-age men, for a month?

"It was fun for me," the A-list star laughed, looking back on the whirlwind month that has now yielded a documentary about the experience titled "Vince Vaughn's Wild West Comedy Show." "I really wanted to get a chance to bring a fun comedy-variety show to as many people's backyards as possible, and because I only had 30 days in my schedule, that's why I didn't take any time off. I only wish I could have played more places. I really like these guys. They're really funny guys."

On its surface, Vaughn's tour starred up-and-coming comics John Caparulo, Bret Ernst, Ahmed Ahmed and Sebastian Maniscalco -- you could call them "The New-School Kings of Comedy." But the surprising thing is that, in addition to Vaughn, that crowded tour bus also contained Justin Long (who recently grossed hundreds of millions with "Alvin and the Chipmunks"), and the filmmaking team of Jon Favreau and Peter Billingsley (currently finishing up [article id="1579965"]"Iron Man,"[/article] one of 2008's [article id="1579340"]most-anticipated blockbusters[/article]).

"I've never been able to be a stand-up [comic]," explained Favreau, who hit it big alongside Vaughn when the duo starred in 1996's "Swingers." "I've done [stand-up] a couple of times, when my improv group wouldn't show up for an open-mic night, and I would be alone, and I wouldn't give up the slot. It's a big thrill when you get to be up in front of a group of people and tell jokes and have people laugh at you, because it's just you and them. But it's a very, very difficult thing."

One of the fascinating aspects of "Wild West" is that it gives you the opportunity to watch four fast-rising comics and then compare them to four funny actors -- Vaughn, Favreau, Long and "Wedding Crashers" co-star Keir O'Donnell -- who perform skits between the sets.

Is it funnier when someone tells a joke or when someone is the joke? Do audiences laugh harder at routines about airline peanuts, dating difficulties and family anecdotes, or big stars playing silly? Don't be surprised if you and your date end up arguing the point after the credits roll.

"It's so hard for me to even answer that," Vaughn shrugged, considering the issue of which is harder to do. "Because I feel like [Favreau, Long, O'Donnell and myself] are really lucky to be doing any of this stuff, so it's not that much of a struggle. ... To get up and do improv sketches, it's a different feeling. Performing live with an audience, you have a different conversation than [with] doing films."

Indeed, Vaughn and Favreau learned a lot when they took to the stage with Long, who ran with a bit that had him mimicking Vaughn's performance in "Swingers." On other nights, O'Donnell would bring back his gay-aspiring-artist act from "Crashers," or Billingsley and Vaughn would read horribly written scenes from the after-school special (about steroids, no less) that first brought them together as co-stars.

"What I do is different because the learning curve is strange, you're learning so many things," writer/director/actor/producer Favreau insisted. "You're learning about making movies, you're learning about how the industry works, and setting things up. It's more of a life journey. Whereas stand-up is more about focusing on a moment in time, that you continuously repeat onstage in front of different crowds, and refine it and sharpen it."

The "Wild West" experience gave four comics the chance to hang with big-time actors, and four actors the opportunity to see what it was like to not have to wait months to find out if a joke makes audiences laugh. And as they traveled 6,000 miles in 30 days, they also learned a valuable lesson about actor-turned-producer Billingsley: When he's sleeping, he doesn't like to be screwed with.

"I almost shot Justin Long," he laughed in retrospect, reminded of a caught-on-tape moment that has the "Accepted" smartass piling boxes on top of a slumbering Billingsley, who awakes with a James Gandolfini-esque rage. "It was like that every night."

Once a child star, Billingsley is now a 36-year-old super-producer -- but even he didn't have enough power to get the embarrassing footage pulled from the flick.

Remembered Favreau: "The stuff that made me laugh [on the tour] was watching Peter Billingsley, who I've produced movies with, getting woken up on the bus by Justin Long, and watching him snap and almost go after him."

"It was a treat to go out with them," Vaughn laughed. "Billingsley was Ralphie in 'A Christmas Story,' and he's my best friend."

"It was real," the subject of their teasing shrugged. "And that's the commitment we made: It was, 'Let's just show our lives, and have this be a snapshot in time.

"Our bus was almost like a prison," Billingsley laughed. "It got a little rough in there for a while."

Check out everything we've got on "Vince Vaughn's Wild West Comedy Show."

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