A rather morbid "game" that I remember from my childhood. One person was instructed to stand up straight with their eyes closed while another person stood behind them, pounding on their shoulders while everyone around them sang this song:

Concentrate....concentrate.
People dying, children crying
Concentrate...concentrate.
People dying, children crying
Concentrate...concentrate.

Stick a knife in your back, let the blood trickle down.
Stick a knife in your back, let the blood trickle down.
(as these lines are said, the person behind the 'victim' hits them with their fist in the back like a knife, and draws the hand down like blood)
Concentrate...concentrate.

After several iterations of this, the pounding would stop and the victim would be told, "On the count of three, you will be pushed off of the Empire State Building. One...two...three!" And they would be given a shove forward.

The alleged point of this exercise was that the person would actually feel as if they were falling off the Empire State Building. While this I can neither confirm nor deny, the whole thing really gave me the creeps when I was ten or so.