Of all the LEGO great ball contraptions I’ve seen, this is the first that can spell out a message. Leave it to the great mind of mahjqa to come up with a Mindstorm-powered device to arrange the balls in a pattern to form letters across a conveyor belt.
Clearly you missed this one:
https://www.youtube.com/watch?v=QyDVdVSGLbs
At the time the builder was a 1st time GBC builder and 16 years old.
Is it actually GBC compatible? Those are Zamor spheres, not soccer balls. Still, pretty amazing.