Top Secret. Also going on Raiders, the guy at the start with Indy who trys to steal his statue in the tunnel with the boulder is Alfred Molina, who plays Dr Octopus in Spidey 2. but then again he’s been in everything.
Law & Order’s Jerry Orbach was the voice of Lumiere, the candlestick, in Beauty and the Beast (1991)
For some reason, I still can’t get over that. Briscoe? As the candlestick?
William Hootkins was “Lt. Eckhardt” in Batman
and played “Porkins” (Red Six) in Star Wars!
I’ve used his name for years to point out the definition of an effective charactor actor. That guy is good. He was also in Raiders of the Lost Ark man, how lucky can a guy get?
I was thinking of something else, but THAT is now my “Holy Crap!” moment.
And I love playing IMDb roulette, where you just keep hitting links and get some very obscure information on actors. Fun way to pass the workday. 
Famke Janssen (X-Men) was in a Star Trek TNG episode, playing Kamala in the episode “The Perfect Mate.” It was her makeup design in that episode that was later turned into the Trill markings, for which Ms. Janssen was also considered (as Dax).
Samuel Jackson was in “Coming to America” as the guy who robs the McDougals restaurant.
Laurence Fishburne was in “Apocalypse Now” when he was only 15.
For me, Alfred Molina is, now and forevermore, Rahad in Boogie Nights. The crazed coke dealer with the Asian houseboy tossing forecrackers around the room. But that’s definittely a “Holy Crap” moment now too. I didn’t realize that was him in Raiders.
My all-time moment is realizing that Danny (the main character) in Caddyshack grew up to be Jackie’s husband Fred on Roseanne. I didn’t even realize that until Roseanne had been off the air for several years.
Also, seeing Jack Black when I saw Dead Man Walking again recently was a jolt. He was a relative unknown (to me anyway) when it first came out. Now I could only think of Shallow Hal when he was emoting on the screen.
That guy who defeated the terrorists in Die Hard was the same bloke who defeated the terrorists in Die Hard II. Holy cow!
Both Laurence Fishburne and Phil Hartman were on Pee Wee’s Playhouse in the '80s - as “Cowboy Curtis” and “Captain Carl”, respectively.
[continued hijack/]
I think it is rather cool myself. 
Sadly, grampa’s wall-vaulting skills were not passed down to me, but my dad did share the family tradition of stunt fighting, fencing and horsemanship. Nothing close to The Matrix or Crouching Tiger…, but I could put on a convincing lesbian bar-brawl…if I could just find a few friends willing to get thrown out with me.
Another of my “cool grampa” stories… He used to have a horse and an elk who were trained to “fight”. They’d put rubber antlers on the elk and film what were supposed to be “white-knuckled scenes of Nature in the Wild West”. [/hijack]
Phil Hartman also co-wrote the script of Pee-Wee’s Big Adventure.
Hey, don’t laugh. I once ran afoul of a rare but vicious rubber-antlered elk. Chased me up a rubber tree, it did. I finally had to shoot him with a rubber bullet.
More proof that I’m newly single, yet fitting for this thread:
I was watching Men with Brooms, and blurted, “Holy cow! That’s TJ Burke from Aspen Extreme!”
Sad, I know.
He’s also the Mountie from the series “Due South.”
Okay, I saw “Silence of the Lambs” once, in the theater, when it first came out, so I’m not really that familiar with the details of the film. There is guy I work with who is in another city and we do conference calls frequently. A woman who works with me freaks out every time she hears this guy’s voice on the conference call because it is really deep and she says it reminds her of the serial killer (Buffalo Bill?) in SOTL. So out of curiosity I went out to IMDB one day to see who the actor was. It’s Ted Levine, our beloved Capt. Stottlemeyer from “Monk”!
C-Square. We could do an entire thread on L&O. The OB-GYN that drugged and molested his patients (including Dr. Olivet) has been in tons of them, all as different characters. So has the guy that was the DA in LA during that three-part episode - he was a somewhat slow husband who knew his wife was killing their babies. “You’re a good person. I just don’t know why you do this.”
Another great one was when I saw Wargames recently. The very first scene, where the two men in the silos get a “real” order to launch the nuclear warheads and one of them pulls a gun on the older man: “Turn your key, sir!” The older man is Tommy Mullaney from LA Law who went on to play Leo McGarry on The West Wing. The younger man is Michael Madsen.
**And ** Edgar, the wife-beater who gets taken over by the alien in Men in Black.
A vague family aquaintence, Robert Foxworth (most recently of Six Feet Under fame) has had 3 different roles in the L&O family. A personal favorite was when he and his son, Bo Foxworth, (a childhood friend of my brother) played the roles of a father and son who were both under investigation in the SVU episode, Misleader.
From what I can tell it must be a pretty great gig to work with those L&O folks. No wonder it is so common for actors to return and cause us those little moments of deja vous.
Bo’s mother, Marilyn, (Robert’s ex-wife) moved he and his sister from LA to my itty bitty hometown in the middle of nowhere Northern California, where she became the Drama teacher at our itty bitty school, and now runs an itty bitty theatre troupe in the next itty bitty town over. We all got to meet Robert briefly when he came up from LA for Bo’s (and my brother’s) high school graduation in the early 80’s, (his Falcon’s Crest days).
The “next itty bitty town over” is Ferndale, California (where we all went to high school) and which has been the location of quite a few large and small screen moments:
Salem’s Lot (1979) (TV)
Blue Skies (1988) TV Series
Outbreak (1995)
The Majestic (2001)
whew! So this is fun…reminds me of the Oracle of Bacon, which is, believe it or not, how I discovered that Grampa Chad The Stuntman was listed in the IMDb…
queue the twilight zone music
Geeking myself out extremely here, but…
“Sheej, Kyle Valenti on ‘Roswell’ was the same guy as Trek on ‘team knight rider’??”
I think that one surprised me so much because they’re such incredibly different characters, almost polar opposites, and yet Weschler played both with such total commitment.
(And, come to think of it, isn’t geeking out practically the point of this thread? 
)
Seth Green – aka Scott Evil from the Austin Powers movies and “Oz” on Buffy the Vampire Slayer, as well as numerous other roles – was Patrick Dempsey’s obnoxious younger brother in Can’t Buy Me Love.
Also, Cynthia Nixon of Sex in the City was the little hippy girl “Sunshine” in the 1980 movie, Little Darlings starring Tatum O’Neal and Kristy MacNicol.
James Cromwell of Babe and L.A. Confidential was Archie Bunker’s buddy Stretch Cunningham on “All in the Family” back in the day.