There is going to be an episode of "The Score" on radio (and online) dedicated to Alan Rickman's roles. I heard just a brief announcement and I'm not sure exactly what date. I'm guessing next Saturday but it could be two weeks out. In any event, once broadcast, it will be available online for a couple weeks at allclassical.org
http://player.allclassical.org/archive/the-score
I started poking around trying to find specifics and ran across the following.
These are some quotes from a 2011 NY Times article about a Broadway play in which AR plays the character Leonard. It sounded so "Snape" I couldn't help but share it. Especially AR's comment about how Snape turned out.
There’s more going on than just mean-spiritedness in Mr. Rickman’s formidable Leonard, an international literary figure who spares no one’s feelings.
The director, Sam Gold’s blocking indicates as much about the characters as the dialogue. While Leonard prowls the room with complete command, his students often huddle in motionless clumps, like petrified lambs eyeing a wolf in their midst.
The mirror effect between the dynamic of the characters and that of the ensemble was not lost on its lead actor. Mr. Rickman said in an interview backstage before a recent performance. “There’s Leonard and these four young writers. There’s also an older English actor with four young American actors, and I think it’s a much more fearful world for young actors now.”
Asked if his director or fellow cast members are intimidated by him, Mr. Rickman, 65, arched an eyebrow. In that voice that evokes a slow pour of black molasses, he said, “You’d have to ask them.”
Play author, Ms. Rebeck, acknowledged that, given the disparity of age and professional experience in the company, a certain degree of awe was inevitable. “Listen, it’s not the warmest or fuzziest experience, working with Alan, and that’s good,” she said. “He’s such a prince of a guy. But he can be scary.”
Merciless though his approach might be, he’s there to steer the students in the right direction. “Leonard’s motives are not ultimately vindictive,” said Mr. Rickman, who knows something about playing moral ambiguity. For 10 years and 8 “Harry Potter” films he has been the face of Severus Snape, the potions master at the Hogwarts School. That raven-haired, sinister figure, as millions now know, turned out to be “unutterably honorable,” to use Mr. Rickman’s words.