I used to date a Mon flight attendant and heard plenty of CAT stories -the nastiest involved a few limbs and a trolly doing a drinks service. That is a heck of a mass to hit the ceiling and come crashing down again (the trolly, that is
)
Also I've flown through my own turbulence whilst doing steep turns on the PPL course - that's quite interesting in a C152. (and yes, yes I know that means I did it wrong)