Peter Brocco, the Organian “Claymere” in “Errand of Mercy,” as crooked contractor “Theophile Duclerc” in Perry Mason’s “The Case of the Fraudulent Foto.” (1959)
Brent Spiner in “Independence Say” as the crazy director of that secret Area 51 facility.
“Independence Say” what? 
More from Perry Mason (the place where I’m currently residing shows episodes back-to-back from 06:00 to 12:00, followed by Columbo until 16:00):
Ken Lynch (Chief Engineer Vanderberg in “The Devil in the Dark”) in “The Case of the Stuttering Bishop,” and Jon Lorman (three “old man” roles in different episodes) as the doctor presenting evidence in the same episode.
WILD CARD: Perennially type-cast Vito Scotti as “D’Amato” in “The Case of the Howling Dog.” (You mention Columbo, you have to include Vito Scotti!)
Jon Lormer was Nathan Grantham in Creepshow (1982) but not Nathan’s shambling corpse. I should have recognized his voice.
Susan (Dr. Leah Brahms, ST:NG) Gibney — recurring role on Crossing Jordan.
Watched a old (94) TV movie called “Without Warning”. Score four Trek actors: Ron Canada (two roles), Alan Scarfe (two roles), Spencer Garret (Simon Tarses) and the biggie John Delancie (Q). Also a cameo of Arthur C. Clarke as himself. (It’s on YouTube for any SF buffs who haven’t seen this one.
A young George Takei (“Mr Sulu” himself) as “Toma Sakai” in Perry Mason’s “The Case of the Blushing Pearls” (1959).