Big Neon signs will always get your attention. Not everyone can afford one however.
Thankfully you can do a LOT of things with affordable LED signs. Here is a demo I put together highlighting some of the things you can do with LEDarcade -- a python project that I have on GithHub.
Make sure to check it out, and if you like come on board and start coming up with your own demos. #Hackathon is on, and this project is participating.