Yes I have seen last month someone trying to pull out their hand luggage and drop it on the head of the passenger sitting and almost knocked her out. The passenger was crying too and you could hear the sound of it hitting her head.
Furthermore, on another flight last month a passenger with a huge back pack on her back when she was boarding and walking thru the aisle almost knocked a passenger down too by turning around and hitting him in the face.
I really do not understand why airlines are so serious about weight yet let these big back packs be taken on board the aircraft.