Dr. Phil McGraw, Tilda Swinton, Tricky

Robin Williams, Shannen Doherty, Duffy

John Malkovich, Hayden Panettiere, Steve Earle

Keira Knightley, Thomas L. Friedman

Jada Pinkett Smith, Chris Russo, Michael Buble

Sen. Barack Obama, LeBron James

Jessica Simpson, Jack Hanna

Meg Ryan, Ricky Gervais

Bill Clinton, Chris Rock

Julianne Moore, Tom Dreesen & Tim Reid, Kings of Leon

Keith Olbermann, Chandra Wilson, Delta Goodrem

Paris Hilton, Usain Bolt, Morningwood

Lance Armstrong, Kristen Wiig, TV on the Radio

Julia Louis-Dreyfus, Michael Cera, Pete Seeger

Anne Hathaway, Josette Sheeran, The Virgins

Kate Walsh, Barry Sonnenfeld, Darius Rucker

Calista Flockhart, Bill Hader, Lucinda Williams

Brian Williams, Tim Robbins

Russell Crowe, Sarah Vowell, The Pretenders

Debra Messing, John Carter, Tegan & Sara

Dennis Quaid, Sarah Chalke, Buddy Guy

Bill Murray, Beck

Jeremy Piven, Elizabeth Banks, Lou Reed

Sarah Silverman, the Teutuls, Ra Ra Riot

Josh Brolin, Amy Sedaris, Blues Traveler

Martin Short, Marv Albert

Sen. John McCain, Ne-Yo

Tina Fey, Frank Caliendo, Tim Montana

Bill O'Reilly, Lauren Conrad

Regis Philbin, James Taylor

Alec Baldwin, Paul Mooney, Ryan Adams

Ashley Olsen, Paul Rudd, John Legend

Marcia Cross, Alan Zweibel

Paris Hilton, Elvis Costello, Jenny Lewis, a Top Ten List by Ricky Gervais

Tom Brokaw, Vera Farmiga

Ben Stiller, Q-Tip

Natalie Portman, Artie Lange, Brad Paisley

Ted Turner, Jamie Oliver, Taylor Swift

Don Rickles, Amy Brenneman, Alicia Keys

Russell Brand, Charlie Haden

Bruce Willis, Sia

Bill Cosby, Matt Braunger

Emma Thompson, Michelle Felicetta, Purple Reign

Carla Bruni Sarkozy, Jack Hanna, Cold Hard Cash

Katie Couric, Dev Patel, Mr. Brownstone

Stephen Colbert, Kristen Stewart, Super Diamond

James Franco, Bruce McCall, The Allstarz

Nicole Kidman, Simon Baker, Kanye West

Reese Witherspoon, Harry Connick Jr.

Teri Hatcher, Ludacris

Denis Leary, John Mayer

Tom Arnold, Faith Hill

Jennifer Connelly, Anderson Cooper, The Duke Spirit

Amy Adams, Michael Sheen, Jamey Johnson

Keanu Reeves, Paula Abdul, Loudon Wainwright III

Sen. John McCain, Bon Iver

Meryl Streep, Jeff Altman

Adam Sandler

Tom Cruise, Fall Out Boy

Jennifer Aniston, Broken Social Scene

Will Smith, Of Montreal

Jerry Seinfeld, Leona Lewis

Dustin Hoffman, Todd Rundgren

Jay Thomas, Mickey Rourke, Darlene Love

Tracy Morgan, Matt Braunger

Kate Hudson, Glasvegas

Kevin James, Becky Quick, Erin McCarley

Ricky Gervais, Rose Byrne, Okkervil River

Kate Winslet, Marv Albert

Kiefer Sutherland, Wendy Liebman

Billy Crystal, Kara DioGuardi

Salma Hayek, Jimmie Walker

Clint Eastwood, Randy Rogers Band

Kyra Sedgwick, Gwen Ifill

Zach Braff, Arj Barker, The Airborne Toxic Event

Brian Williams, Ben Kweller

Evangeline Lilly, Seth Meyers, Andrew Bird

Lauren Graham, Guy Fieri, MENEW

Renee Zellweger, Tony Dungy, Graham Nash sits in with the band

Mary Hicks, the Gaslight Anthem

Ben Roethlisberger, Steve Martin

Rod Blagojevich, Richard Jenkins

Joe Torre, Demetri Martin, Lyle Lovett and John Hiatt

Isla Fisher, extreme fisherman Matt Watson, Mark Olson and Gary Louris, a Top Ten List presented by Lil' Wayne

Dakota Fanning, Keith Alberstadt, Beirut

Naomi Watts, Danny McBride, 2009 Sports Illustrated Swimsuit Issue cover reveal

The crew of US Airways "Miracle On The Hudson" Flight 1549, Heartless Bastards

Joaquin Phoenix, Bar Refaeli, Anthony Hamilton

Chris Russo, the Jonas Brothers, Ashford & Simpson

Martha Stewart, Jake Johannsen, Matt Nathanson

Ellen Pompeo, Daytona 500 winner Matt Kenseth, Willie Nelson with Asleep at the Wheel

Bonnie Hunt, M. Ward

Donald Trump, Antony and the Johnsons

David Spade, Jeffrey Sachs, David Sanborn with Sam Moore

Barbara Walters, Mike Birbiglia, Shemekia Copeland

Katie Couric, U2

Felicity Huffman, Artie Lange, U2

Dr. Phil McGraw, U2

Jon Stewart, U2, a Top Ten List featuring 10 Team USA members from the World Baseball Classic

Jason Segel, Brian Kiley, U2

Russell Brand, Jack Hanna

Stupid Pet Tricks, Paul Rudd, Razorlight

Tom Brokaw, An Horse

Andy Samberg, Paul Teutul Sr., the Broadway cast of "West Side Story"

Will Ferrell, Cursive

Nicolas Cage, Rachel Maddow

Julia Roberts, Bell X1

Craig Ferguson, Ginnifer Goodwin, Modest Mouse

Billy Crystal, Kara DioGuardi, a Top Ten List presented by Owen Wilson

David Spade, Richard Zoglin, David Sanborn and Sam Moore

Hugh Laurie, Bloc Party

Mary Tyler Moore, Blake Lively, White Lies

Christina Applegate, Jim Gaffigan, Jesse Harris with Norah Jones

Seth Rogen, Tom Dreesen, Adele

Bill O'Reilly, Marianne Faithfull

Marg Helgenberger, Francisco Palacios, Ray LaMontagne

Michael J. Fox, the Fray

Denis Leary, Diana Krall

Zac Efron, Mike Golic and Mike Greenberg, A.C. Newman with Nicole Atkins

Kelly Ripa, Bill Scheft, Yeah Yeah Yeahs

Drew Barrymore, Jack McBrayer, Neko Case

Matthew Perry, Elisha Cuthbert, Rascal Flatts

Russell Crowe, Joe Wong

Jeff Goldblum, Jeff Dunham

Nathan Lane, Tinted Windows

Beyonce, Jim Parsons

Jamie Foxx, Lauren Conrad, the Dead

Michael Keaton, Lily Allen

Matthew Fox, Carol Leifer, the All-American Rejects, a Top Ten List presented by Matthew Stafford

Dolly Parton, Zachary Quinto

Jennifer Garner, Tesla Motors CEO Elon Musk, Manchester Orchestra

Regis Philbin, a performance by the Broadway cast of "Hair"

Kiefer Sutherland, Jim Norton, Bat for Lashes

Gordon Ramsay, Chris Pine, Keri Hilson with Kanye West

Liev Schreiber, Dr. Sanjay Gupta, Franz Ferdinand

Bruce Willis, Ben Harper & Relentless7

Norm MacDonald, a Top Ten List presented by Leonard Nimoy, Animal Collective

Matthew Broderick, Brian Regan, Chris Cornell

Tom Hanks, the Killers

Alec Baldwin, Maya Rudolph, Chrisette Michele

Robin Williams, Wynton Marsalis

Kid Scientists, Teri Hatcher, Rick Ross with Magazeen, a Top Ten List presented by Ron Howard

John Goodman, Tommy Tiernan, Mastodon

Ben Stiller, White Rabbits

Jane Fonda, Piedmont Bird Callers, Kenny Chesney

Stephen Colbert, General Motors Vice Chairman Bob Lutz, Grizzly Bear

Amy Sedaris, Ed Helms, Jean Redpath

Ricky Gervais, Green Day

Bill Cosby, Helio Castroneves, Melody Gardot

Jack Hanna, John Krasinski

Jessica Biel, Zach Galifianakis, Steve Earle

Elvis Costello, a Top Ten List presented by Neil Patrick Harris

Paris Hilton, Calvin Borel, Steven Wright

Howard Stern, Mos Def

Julia Roberts, Black Eyed Peas

Kathy Griffin, Stupid Human Tricks, Sonic Youth, an NBA Finals report by Phoenix Suns' Steve Nash

Denzel Washington, the Jonas Brothers, a Top Ten List with Regis Philbin

Sandra Bullock, Pete Correale, P.J. Harvey & John Parish

Jack Black, M.A. Sanjayan

Michelle Pfeiffer, Judah Friedlander, Ian McLagan & the Bump Band

Ryan Reynolds, Padma Lakshmi, the Eels

Danny DeVito, Bear Grylls, Phoenix

Jada Pinkett Smith, Michael Cera, the Sounds

Samuel L. Jackson, Emeril Lagasse, Iggy Pop & the Brighton Port Authority

Sandra Day O'Connor, MSTRKRFT with John Legend, a Top Ten List presented by Lucas Glover

Ray Romano, St. Vincent

Johnny Depp, Megan Fox

Martin Short, Regina Spektor

Serena Williams, Hayden Panettiere, Conor Oberst and the Mystic Valley Band

Sacha Baron Cohen, Joel McHale

Queen Latifah, Emma Watson

Daniel Radcliffe, Veronika Part, Levon Helm, a Top Ten List presented by Bruno

Rainn Wilson, Larry Miller, Maxwell

Jonah Hill, Gar Ryness, Kelly Clarkson

Edie Falco, Michael Showalter, Wilco with Feist

Paul McCartney, a Top Ten List presented by Bruce Willis

Anderson Cooper, Anna Paquin, Grizzly Bear

Tom Arnold, Metric, a Top Ten List presented by Dave's mom Dorothy

Katherine Heigl, Jeff Altman, Spinnerette

Kevin Spacey, Jesse James, the Flatlanders, a Top Ten List presented by Stewart Cink

Tracy Morgan, Leslie Mann, Diane Birch

Sean "Diddy" Combs, Vera Farmiga, Ginuwine with Missy Elliott

Amy Poehler, Nick Griffin, Judy Collins

Eric Bana, Dave Matthews Band, a Top Ten List presented by Chicago White Sox star Mark Buehrle

Katie Couric, Silversun Pickups

Amy Adams, Tom Dreesen, Elbow

Adam Sandler, Cage the Elephant

Regis Philbin, Ted Alexandro, Dave Matthews Band

Quentin Tarantino, Eric Ripert, Robert Cray

Donald Trump, Diane Kruger, Billy Currington, a Top Ten List presented by Britney Spears

Mike Myers, Ken Burns

Anna Wintour, Mark Teixeira

Renee Zellweger, Gary Mule Deer

Christina Applegate, Brendan Benson, Patton Oswalt

Anna Wintour, Mark Teixeira

Mary-Louise Parker, Eugene Levy, Jet

Anne Heche, Jim Parsons, Care Bears on Fire

Andy Roddick, Rachael Ray, Mutemath

Artie Lange, Todd Barry, Imogen Heap