When on vacation this summer I had found some plastic letters in a junk shop.
I decided to make the following sign and finally finished it.
I used a stand alone Arduino and 2 TLC5940 chips. The sign has a photo resistor and only comes on when dark enough.
The sign also has a momentary push button to toggle through different modes.
Current modes include light one led at a time until all are lit, blink all and fade up and down.
For a video & more details check out http://electricprojects.wordpress.com/2013/10/01/eat-sign-done/