Disney and Universal don't usually promote these cameos beyond the rides' opening months, and IMDB.com doesn't list theme park attraction appearances, so there are rarely public reminders that these shadow credits exist on their résumés. And since taking photos is usually forbidden, the only images we have of these under-the-radar gigs are the ones that were surreptitiously shot by fans as they avoided being spotted by ride attendants.
So who's has starred in Orlando's biggest attractions? We'll show the outside of each one, followed by the star who has been seen surprising guests within—the photos were taken by fans eager to put these under-the-radar appearances on the record.
Jason Cochran is the author of Frommer's EasyGuide to Walt Disney World & Orlando.

BR WDW/Flickr
Universe of Energy, Epcot, Walt Disney World

Loren Javier/Flickr
Ellen DeGeneres
Attraction: Universe of Energy (Ellen's Energy Adventure), Epcot, Walt Disney World (1996–2017)Role: Herself, in a dream, playing 'Jeopardy!". Co-stars: Alex Trebek, Jamie Lee Curtis, Bill Nye The Science Guy.
Sample line: "Now some person I don't even know reminds me there's no eating, drinking, smoking, or flash photography allowed in my dream."

rickpilot_2000/Flickr
Soarin' over California at Disney California Adventure & Soarin' at Epcot, Walt Disney World

Loren Javier/Flickr
Patrick Warburton
Attraction: Soarin' over California at Disney California Adventure; Soarin' at Epcot, Walt Disney WorldRole: Patrick, "Your Chief Flight Attendant."
Sample line: "If smaller aviators don't measure up to the height indicator on the seat, just put the belt through the loop in the center strap before buckling it."

mrkathika/Flickr
Dinosaur, Disney's Animal Kingdom, Walt Disney World

Loren Javier/Flickr
Phylicia Rashad
Attraction: Dinosaur, Disney's Animal Kingdom, Walt Disney WorldRole: Big boss of the Dino Institute. Co-star: Wallace Langham
Sample line: [stacotto, Claire Huxtable-style] "In a perfect blend of science and technology, the Dino Institute has created The Time Rover."

mrkathika/Flickr
Mission: SPACE, Epcot, Walt Disney World

Sam Howzit/Flickr
Gary Sinise
Attraction: Mission: SPACE, Epcot, Walt Disney World (2003–2017)Role: Astronaut trainer at the International Space Training Center
Sample line: "I know you're probably feeling a little bit nervous right now, but don't worry. Every astronaut has felt that way one time or another."

Universal Orlando Resort
Men In Black Alien Attack, Universal Studios Orlando

Will Smith
Role: Agent J from the Men in Black franchise
Sample line: "You people are M.I.B. material!"

Christian Lambert Photography
Rock 'n' Roller Coaster, Disney's Hollywood Studios, Walt Disney World & Walt Disney Studios, France

Loren Javier/Flickr
Steven Tyler
Attraction: Rock 'n' Roller Coaster, Disney's Hollywood Studios, Walt Disney World & Walt Disney Studios, FranceRole: Himself, running late to a gig. Co-stars: Aerosmith and Illeana Douglas (Orlando version)
Sample line: [Looking toward the guests in line] "Wait a minute. We can't leave these people here like this!… How about some backstage passes?"

Raw Processor/Flickr
Pirates of the Caribbean, Disneyland & Walt Disney World

Disney Parks
Johnny Depp
Attraction: Pirates of the Caribbean, Disneyland and Walt Disney WorldRole: Captain Jack Sparrow, Audio-Animatronic style
Sample line: "Drink up, lads. There's treasure enough for all!"

Roller Coaster Philosophy/Flickr
Disaster!, Universal Studios Orlando

Roller Coaster Philosophy/Flickr
Christopher Walken
Attraction: Disaster!, Universal Studios Orlando (2007–2015)Role: Frank, a disaster movie director
Sample line: "People come up to me every day, they say, 'Frank, why do you only make disasters?' Why did Picasso cut off his ear? I don't know!"

HarshLight/Flickr
Imagination!, Epcot, Walt Disney World

BarryWallis/Flickr
Eric Idle
Attraction: Journey into Imagination, Epcot, Walt Disney WorldRole: Dr. Nigel Channing from the Honey, I Shrunk the Kids franchise. Co-star: Voice of Dave Goelz (the Muppets' Gonzo)
Sample line: "So, as you can plainly see, imagination works the best when it's set free."

Universal Orlando Resort
Harry Potter and the Forbidden Journey, Islands of Adventure, Universal Orlando

Universal Orlando Resort
Daniel Radcliffe
Role: Harry Potter. Co-stars: Emma Watson, Rupert Grint, Tom Felton, Robbie Coltrane, Michael Gambon. This is the rare ride appearance that is well-publicized.
Sample line: "Sorry about that! Those benches can be a bit dodgy. But we haven't lost anyone yet."

daryl_mitchell/flickr
Revenge of the Mummy—The Ride, Universal Studios Orlando

Brendan Fraser
Attraction: Revenge of the Mummy—The Ride at Universal Studios OrlandoRole: An nasty version of himself asking riders if they had fun
Sample line: "It would have been even better if I'd gotten my cup of coffee!"

Disney Parks
O Canada!, Epcot, Walt Disney World

Martin Short
Attraction: O Canada!, Epcot, Walt Disney WorldRole: Himself, as host of an 18-minute film about Canada
Sample line: "Here in Nova Scotia, our passion is sailing. This is the home of the legendary Bluenose, winner of four international races in her day. We're so proud of her we put her image on a coin. Check it out the next time you accidentally get a Canadian dime in your change."

Frommer's
Frommer's EasyGuide to Walt Disney World & Orlando