In The Music Box they spend the first half of the film getting a piano up a rather large flight of stairs. When they finally reach the top, a postman tells them they could have just gone around and up a nearby hill. So what do they do? They take the piano all the way back down and go round.
In Way Out West Stanley vows if they don't succeed in their task "I'll eat your hat!" When they don't succeed, Ollie makes him stick to his word. Initially whimpering in distaste at the deed, Stanley's lapsed into blank-faced contentment by the third bite of his meal. Ollie snatches his hat back before it's completely gone, but takes a curious bite himself.
In Block Heads Ollie invites old war buddy Stanley to his home. Before long, Stanley's destroyed Ollie's car, the wife has left in a huff, and the apartment is destroyed. Ollie tries using the phone, unaware the line's been severed, and after a long conversation realizes he's been talking to Stanley...Ollie chuckles merrily, then throttles him.
In Blotto, the entire phone conversation between Laurel and Hardy while Laurel's wife is in the same room. Laurel hangs up twice on Hardy, Hardy keeps trying to find Laurel's number in a phone book, and the slapstick during the third time they're talking. Also including the duo's reactions to the liquor (which was really cold tea with tabasco and various substances Laurel's wife put in), Laurel randomly bursting into loud tears while someone sings, and the last several minutes from the two laughing hysterically to them being chased by Laurel's wife, who is wielding a shotgun.
The "Jeanie-Weenie" running gag in Beau Hunks, particularly where even the leader of the invading force has a photo of her.
At the beginning, after a montage of Ollie's house after a wild party, we see him giving "The Reason You Suck" Speech to somebody. That somebody is his reflection in the mirror.
Ollie getting his head caught through a drawer.
Stan deciding to light a fire for when Mr. and Mrs. Hardy get home. The fire won't light, so he pours some kerosene on the logs. Cut to a bit later, the house burnt down.