I noticed another bit of Curly-on-Moe violence in
Yes, We Have No Bonanza. In addition to the already-mentioned bit in which Curly picks up a large rock, hefts it, then throws it at Moe, striking him squarely and resoundingly on the head, there is a bit in the saloon in which Curly, in retaliation for an eye-poke, uses the old hand-wave to get Moe's head back then lifts his bangs off his forehead and squirts him in the eyes with seltzer. It's at 6:25 in the video below.
The great rock shot is in part 2, around 0:35:
I think that throw, and the sound effect used for the rock bouncing off Moe's head, make me cackle more consistently than any other bit in the Stooge shorts.