Having studied art in college, as opposed to business, Mike Richardson considered himself an unlikely entrepreneur when he launched Dark Horse Comics in 1986. But the name he chose for his venture has since proven apropos for another reason: The privately held concern, located in remote Milwaukie, Ore., has become the third largest comics publisher in the U.S., last year raking in about $30 million in sales. (Based on revenue, Marvel Comics is No. 1 and DC Entertainment is No. 2, according to Austin, Texas, research firm, Hoovers Inc.)

And...