It's similar to Ease and Wizz - but with sliders to adjust amplitude, decay, and frequency.

The expressions simply check the velocity of your animations. If you move an objects motion ends abruptly (ie: you didn't easeIn @ 100%) the physics will kick in automatically.

Use Quick Gravity to add a falling and bouncing effect to a layer or layers in your composition quickly and easily.

Make your layer bounce as if off of a floor.

Essentially, Inertial Bounce creates a bouncing motion of any parameter from one keyframe to the next, based on its velocity.

These expressions save so much time, you might get home earlier tonight just by reading this.

Emit lots of footballs and make them bounce in After Effects. Trapcode Particular bounce option will be the weapon of choice

Ease and Wizz is a set of expressions for After Effects that give you more ways to interpolate between values. This new version lets you apply the expressions to curved motion paths and mask shapes.

Creates a bouncing (sine wave) motion between two specified 2-dimensional positions over a
specified period of time (in seconds). Useful for creating bouncing balls.