Brahmin tipping

Brahmin tipping seems to be an Easter egg in Fallout 2 and 3.

Fallout 2
Tipping can occasionally be acheived by selecting the palm icon in the drop-down menu that appears when a person or item is click-held, however this will also sometimes simply "move" the brahmin. Performing this action inflicts no damage to the brahmin.

Fallout 3
By crouching near a Brahmin and pressing the activate button you will push the brahmin over, causing it to go into a ragdoll state and getting back on it's feet in a couple of seconds. You will not lose any Karma for doing this, nor will anyone or anything become hostile. Be warned that repeating this action may cause the Brahmin to die. Even after it dies, no one becomes hostile and you do not lose karma. You may also loot the body for Brahmin Steak.