Frank Caliendo

Is that John Madden, Dr. Phil, Charles Barkley, Robin Williams, Al Pacino, Bill Clinton and George W. Bush in the studio at the same time? No, it's just comedian and impressionist Frank Caliendo, but we can see where you'd be fooled. Caliendo was the star of the TBS show, "Frank TV," has appeared on a number of late night programs, had his own Vegas show for many years, and is the new comedic component of ESPN's Sunday NFL Countdown. Follow Frank on facebook and twitter.

Nick Griffin

Nick Griffin began doing standup comedy back in 1987 as a way to voice his frustrations with life and to avoid having a job with a boss. Sure he may be dark, cynical, depressed and has a problem getting along with women, but Griffin is one of our absolute favorite guests and is a must see if he performs in a club near you. Nick has been featured on Comedy Central's "Premium Blend," "The Late Show w/ David Letterman," "The Late Late Show w/ Craig Ferguson" and recently finished a brand new comedy CD "Bring Out the Monkey." Follow Nick on twitter and facebook.

Scott Dunn

Scott Dunn is a stand-up comedian, a novelist, a father of two, and a husband of one. He's also a full-time history buff, and famous for his roasts of famous historical figures and events. He also occasionally calls in with History Lessons and Quizes, which means if you see his name on the guest board, you'd better start studying. In his spare time (when he's got any) he writes jokes for a number of shows including "Are You Smarter Than a 5th Grader." And that's a little bit about Scott Dunn.