Keeper of the Superfluous Es!

I've always thought that Snape wasn't a Quidditch player, and OotP kind of clinched it for me. In the pensieve is a memory of a girl laughing as he tries to mount a bucking broomstick, and when Remus is trying to explain to Harry that Severus was jealous of James, he cites that James was good at Quidditch. It's nothing concrete, but the image we get of him as a boy seems to be rather more academic than athletic.

(Just my two cents.)