Adobe After Effects Tutorial -- Connect The Dots: Simple Expression + Beam Effect
This tutorial shows how to use a simple pick-whip expression to connect the ends of the Beam effect to Null Objects in order to animate a technical-style line bookended by two dots.
This is useful for adding animated text callouts in a video or to simply point to something that's moving. This also shows the power of AE effects, solids and nulls in creating animations without any external assets.