- Create a Light Wall: tutorial & preset and Scrolling LED Text in After Effects (pictured; more involved with expressions) by Quba Michalski
- Creating an LED sign in After Effects by Shortformvideo
- Creating Automated Flashing Light Patterns from RGTV
- 3D Ball Dispersion with CC Ball Action from Andrew Kramer
- Scrolling LED Text in After Effects from Quba Michalski
- Jumbotron in After Effects by Motionworks, Rabinowitz, and Maltaannon. School of Motion posted Making Content for Jumbotrons, about arranging for multiple screens.
- The Dot Pixels plug-in from Satya Meka at AE Scripts is useful to create LED screen effect, a porous surface effect, or abstract art. He later added TVPixel, a plug-in for After Effects and Premiere Pro, for a similar effect.
- LCD + video game looks discusses the LCDeffect script at AE Scripts by Tatsuro Ogata.
- Optical Flares comes with an advanced tutorial that builds a light wall
- Switch On This Casino Style Text Effect Tonight uses Video Copilot Optical Flares on a ton of layers and CC Particle World to create a distinctive look (preview below).
Many of the tutorials use the built-in CC Ball Action filter, which “transforms the source layer into an array of balls. You can rotate and twist the array around a specified axis and scatter the array in all directions.” Ball Action is a very old filter that hasn't been upgraded beyond support for the AE comp camera, but using the Brighten Twist control makes things interesting beyond the basics described by the intro by Brian Maffitt from an old Total Training video at Toolfarm.
See also Bullet Riddled Text from CG Swot which uses Particular to create something not so different.
Update: Pixel Screen Experiment! from Andrew Kramer an experiment (with project file) that simulates LCD Pixel effects using built-in plug-ins like Ball Action and Camera Lens Blur with a depth map to create realistic DOF.