Harry spun on the spot, lost balance, and nearly fell over.  He was not the only one.  The whole Hall was suddenly full of staggering people; Neville was flat on his back; Ernie Macmillan, on the other hand, had done a kind of pirouetting leap into his hoop and looked momentarily thrilled, until he caught sight of Dean Thomas roaring with laughter at him.

Harry Potter and the Half-Blood Prince – J.K. Rowling