Perhaps the most interesting example of this is actress Hedy Lamarr, who during World War II invented and patented a Secret Communication System.
Former San Francisco 49ers QB Steve Young has a law degree. Then again, it probably helps to be a descendant of Brigham Young (BYU!)
Mira Sorvino graduated magna cum laude from Harvard with a degree in East Asian Studies.
Cindy Crawford was valedictorian of her high school class and was working on her Chemical Engineering degree at Northwestern University. However, she decided to drop out and continue her modeling career before graduating. Must have been a dark day in Northwestern’s engineering classes (“What do you mean, Cindy dropped out? I finally worked up the nerve to ask her to come back to my room to see my Star Trek figures.”).
Mick Jagger graduated from the London School of Economics, which is one of the premier (top four in the world, says the link) academic institutions in the world. Cite.
Someone checked into that, and Lewis has no such degree from Columbia.
Speaking of that school, Nat Pendleton, who made a career of playing big dumb lugs in Hollywood movies of the thirties and forties, graduated from Columbia U., majoring in economics.
He did claim it, however. He’s also claimed that he’s a Gypsy (false), that he’s from Russia (false) and several other odd statements. He’s basically a pathological liar (but a charming one).
Johnny Depp use to be in a band called “the Babies” that opened for…uh…I can’t remember, but it is someone recognizable.
Governor Schwarzenegger use to be in the movies. Really. 
Glenda Jackson who is/was in parliment, use to be an actress in movies.
Ooooh, there’s a good one. Besides being the Governator, Arnold is a successful businessman.
Sir Mick did indeed attend the LSE, but never graduated, choosing instead to make approximately eleventy bazillion dollars in the music industry. Which means, of course, that maybe he didn’t have to go to school to know a lot about economics.
Fred “Herman Munster” Gwynne graduated from Harvard as an arts major. He was also editor of the Harvard Lampoon, and an accomplished artist and writer.
Asia Carrera, the quintisential Asian porn star, graduated at the top of her class in high school (may have been valedictorian,) and attended Princeotn on a scholarship until she dropped out to pursue her career. She is a member of Mensa, and a huge computer and gaming nerd.
I believe that Tom a tually taught Chem. E. at MIT.
–Cliffy
She was also a child prodigy on piano, and played Carnegie Hall at a young age.
Last time I checked, about six years ago, Dexter Holland from the Offspring was working on his PhD in BioChem from Caltech.
Based on the thread title, I opened this thread solely to mention Dolph Lundgren.
I met him on a movie shoot in 1990 at one of the engineering labs at Rice University. I happened to bump into him in the hallway between takes, and spoke with him for a few minutes. He asked me what I was majoring in, and I told him that I was getting a degree in chemical engineering. He replied, “No kidding; I’ve got a degree in chemical engineering!” He said that he had done some modeling and acting on the side while at his university, but never expected his career in entertainment to take off. He said that he made a point of finishing his degree so as to have a fall-back career.
Anyway, he was really pleasant to talk to; he wasn’t full of himself or anything. Nice guy.
Louis Wolheim (the actor who played Katczinsky in All Quiet on the Western Front) was known for his crude looks, but was Cornell-educated.
IIRC, he taught mathematics there for a while. I remember this, because there’s a line in AQOTWF where the young, idealistic recruit is reading aloud about geometric series from a math book, and Katczinsky admonishes him, “Whaddaya wanna learn all that stuff for? One day you’ll stop a bullet and it’ll all be wasted”.
The Governator graduated from University of Wisconsin-Superior with a major in international marketing of fitness and business administration. [1979] I think it was a correspondance-type deal. (insert joke about harsh northern Wisconsin climate)
Brian
Milo Aukerman lead singer of the punk band The Descendants has a PhD in BioChemistry, and mnakes albums and tours in-between doing research work at the Univeristy of Wisconsin’s Amasino Lab.