I am generally thought of by colleagues as a bright hacker with good ideas and implementation. What I suck at is speaking publicly. What course would make me build this skill better?
As an MBA and actor, I'd advise an improv comedy course! Stand-up is great, but, doesn't teach you the importance of listening and playing off of others, which is pretty critical to speaking well, imho.
Stand up comedy. As a business school graduate, I can say that there aren't enough courses doing speaking. I'm signing up for an improv course next month so that I can get better.