Any game with ragdoll physics can keep me entertained indefinitely.
Case in point, Hitman; dragging people through narrow doorways, too narrow for their limbs to fit without bending backwards into impossibly awkward positions. "Sure you can do the splits,
see? Easy!"
Other than that...
Final Fantasy 7. There's this one place, right at the beginning of the game, where several NPCs are supposed to run ahead of you through a door into the next area. I take a shortcut and block the doorway. They get stuck. I lol.
Assassin's Creed. Using the "Gentle push" action to harrass people. It makes Altair/Etzio pat women's boobs. Pointless, but hilarious, and the little 'pat' sound effects make it even better.

The Witcher. Running past people makes Geralt shove them out of the way. Rinse and repeat on the same NPC to completely stall them from reaching their destination.
Thief 3. Dropping oil flasks. Due to an engine physics bug, persuing NPCs who trip over tend to go flying forward at top speed, making this especially hilarious if triggered near a flight of stairs.