With this preset you can cause the opacity of a layer to control the brightness of a "Lens Flare".

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.

Auto-orientation towards the camera is a 3D technique in After Effects with a lot of uses. Sometimes though, it would be better if the auto orientation only affected the layer's y axis.

This allows you to control the angle of view of a camera interactively, by scaling a null object
on screen.

The illusion of making something go up in smoke tends to be popular all the time.

Interactively control camera focus distance.
The camera will focus wherever your null or solid happens to sit. This expression is golden when you're doing a lot of Depth of Field work.

Projectfile with a default camera, parented to 2 null objects and a master controller

This collection of scripts is used to transfer 3D motion to and from After Effects, Maya, Nuke, SynthEyes and Electric Image.

This expression maintains the objects apparent size as it moves away from camera.
It's helpful for taking a flat layout and making a "multiplane" layout from it for animation.

This will make your layer/object bounce along an imaginary 'floor'. Paste it into the 'position' attribute for your layer.