Danger Working Sign

Found a sign, mad sense to do something different with it. Initially I was thinking about using an Arduino, but then thought it would be more interesting to make the back-light LED's fade in and out using a 555 times and a few other components.

Total cost around £3 for the components.. And the sign looks cool.. ... https://www.youtube.com/watch?v=HYPrwW6mdZw