A past-time enjoyed by many around the Yorkshire area. Involves "cruising" in a car, with the windows down and music being played at large volume. Participants then "crunk" at passing citizens, preferably those of a more mature age in order to gain a similar, gangsta-style reaction.
Maisie: Yo, Eliza! Holla at me when you wanna go Grannycrunking, yeah?!
Eliza: Sure thing, mo'fuckaaa!