I know him from The New Guy; and a recurring role on Supernatural; and Comic Book Villains; and The Man in the High Castle.
I know him from Heroes; and Star Trek; and AHS: Murder House (and Asylum).
I know him from Harry Potter; and Miracle Workers; and What if. He voiced Edmund in Treehouse of Horror XXI. And he's done a number of things I want to see.
I know him from Xena: Warrior Princess; and Darkman; and the Evil Dead movies; and the Spier-Man movies; and My Name Is Bruce; and The Grudge; and the short film Semblance.
I know him from The Wizard; and Time Bandits.
I mainly know him from Cheers But there's also an ep of My So-Called Life; and M.A.N.T.I.S.; and Veritas: The Quest; and a bit of Warehouse 13; and A Christmas Carol; and A Midsummer Night's Dream; and a small role in The Scorpion King (though I didn't recognize him at all in that).
I know him from the Bill & Ted movies; and Bram Stoker's Dracula; and The Matrix movies; and Something's Gotta Give; and Speed; and Constantine; and A Scanner Darkly; and The Neon Demon; and John Wick.
Reilly, John C.
I know him from Chicago; and The Aviator; and A Prairie Home Companion; and Guardians of the Galaxy; and Cirque du Freak; and some voice work.
I know him from Mad About You; and Aliens; and an episode of Saturday Night Live; and season 2 of Stranger Things; and probably some stuff I've forgotten.
I know him from 28 Weeks Later; and The Unusuals; and The Avengers (and other movies in the MCU); and Hansel & Gretel: Witch Hunters; and American Hustle; and Arrival.
Rennie, Callum Keith
I know him from Due South; and Battlestar Galactica; and The Butterfly Effect; and Tin Man; and The X-Files: I Want to Believe; and undoubtedly other things that I've forgotten.
I know him as Pee-wee Herman from Pee-wee's Playhouse; and Pee-wee's Big Adventure; and Back to the Beach. I also know him for other roles, including a minor part in Batman Returns; and Mystery Men; and the original Buffy the Vampire Slayer movie; and an episode of Everybody Loves Raymond; and an episode of 30 Rock; and a couple eps of Gotham. And he voiced Lock in The Nightmare Before Christmas; and Max in Flight of the Navigator; and Fife in Beauty and the Beast: The Enchanted Christmas.
I know him from The Odyssey; and Sabrina the Teenage Witch; and Two Guys, a Girl and a Pizza Place; and Waiting...; and Definitely, Maybe; and Adventureland; and X-Men Origins: Wolverine; and Green Lantern; and Fireflies in the Garden; and Van Wilder; and R.I.P.D.; and Life. Also voice work in The Croods.
I know him best for Sliders; but there's also the Lord of the Rings trilogy; and a couple of Indiana Jones movies; a couple eps of Star Trek: Voyager; a few eps of Krod Mandoon; and voice work in Aladdin & the King of Thieves and Gargoyles.
I know him from Davis Rules; and several episodes of The Wonder Years; and an ep of The X-Files; and a few eps of Friends; and Sky Captain and the World of Tomorrow; and Avatar; and maybe some things I've forgotten.
I know him from Nature of the Beast; and a few Roxy Hunter TV movies; and a few episodes of Supernatural; and a minor role in Percy Jackson: The Lightning Thief; and Urban Legend; and a minor role in The Last Halloween; and a minor role in A Christmas Horror Story. He's also in Wrong Turn, but unrecognizable.
I know him from Dogma; and Galaxy Quest; and Robin Hood: Prince of Thieves; and Quigley Down Under; and Sweeney Todd; and the Harry Potter movies. He also did the voice of Marvin in The Hitchhiker's Guide to the Galaxy; and he narrated The Boy in the Bubble. Anyway, he's tremendously good at playing annoyed people. (But I think I sometimes confuse him with David Warner.)
I know him from Oscar; and Middle Ages; and The Mask. And I feel like I must have seen him in some other things, even minor guest roles or something, but I might be wrong, because I don't see anything else on IMDb that rings any bells. But I liked him in the few things I do remember.
I know him best from Three's Company, of course. But there's also Hooperman (which I barely remember), and It, and an episode of The Cosby Show, and Stay Tuned, and Hearts Afire, an episode of Buffy the Vampire Slayer, 8 Simple Rules (which I barely watched and didn't care for), and undoubtedly I saw him in some things I don't remember him from.
I know him from the Doctor Who TV movie; and Heroes; and The Dark Knight; and DOA: Dead or Alive; and The Expendables; and an ep of Brooklyn Nine-Nine; and Inherent Vice; and some voice work. And, damn, I feel like I must've seen him in other stuff, I just don't remember...
I know him from NewsRadio; and a minor role in Crocodile Dundee II; and Bicentennial Man; and True Blood; and a few episodes of Brooklyn Nine-Nine; and Get Out; and some voice work. And... looking at a list of his credits, there are a bunch of things I have seen him in that I don't specifically remember him from. But undoubtedly I enjoyed his work at the time, and if I saw any of those things again, I'd be like "Oh yeah, how the heck did I forget about that?"
I know him from Smallville; and a small role in Midnight in the Garden of Good and Evil; and Cursed; and the first season of Breaking In; and Urban Legend; and some voice work.
I know him from Ferris Bueller's Day Off; and Star Trek: Generations; and Spin City; and I Love You, Beth Cooper; and The Whispers; and The Exorcist; and I've seen him in several other things from which I don't remember him.
I know him from The Fire Next Time; and Clueless; and Romeo + Juliet; and The 40-Year-Old Virgin; and I Could Never Be Your Woman; and Forgetting Sarah Marshall; and The Perks of Being a Wallflower; and Ant-Man; and probably some things I've forgotten. Also some voice work, including Monsters vs. Aliens.
I know him from Escape from New York (and Escape from L.A.); and Big Trouble in Little China; and Overboard; and Dreamer; and Death Proof; and Guardians of the Galaxy vol. 2; and maybe some other stuff.