I love Vestaboard. Its delightful & unique. You can create and send your own personalized messages or design your own art to display on the board. Their app has a bunch of channels that you can add to programmatically update on cue, ranging from practical info (today's weather) to more quirky/fun (Monty Python quotes, '90s lyrics, Rainbow art, etc etc). Well engineered & high quality product, and customer support was excellent too.
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Not a complaint because its a complex piece of hardware / software but its definitely an investment!