I've known two people who went to clown school and they both have just incredible comportment & composure. Extremely self-assured, naturally using subtle aspects of positioning and body language to make people comfortable, draw others into conversation and reassure them that their participation is valued.

They both have clearly playful senses of humor once you get to know them, and a lot of surprising little physical, verbal, and musical skills. But neither has that, ahem, "class clown" center of attention type personality. They're just confident, socially skilled, well liked people, one of them is one of the most effective managers I've ever known.

It's long made me wonder what they teach at clown school. When I was reading through this list, thinking of these two, I kept going "ahhh I see." Maybe they were like this before the school, probably were to some extent. But it's also kind of foolish to think several years of focused study on how you can use your body to affect people's perception of your actions would bear no fruit.