I've been building an Internet Connected Fundraising sign using an Arduino Mega and Xbee communications with a Raspberry Pi. Check out the Instructable!
Cunning. Very nice.
Hopefully not too dazzling for road users, but I'm sure you thought of that and positioned it appropriately- looks like a parking area?
Thanks, glad you liked it.
Dazzling drivers was a big concern. We've got two of the signs, and they are positioned along the road so that they can be seen by the traffic. The lights only run at full power during the day. In late afternoon/early morning, they dim down to 50%, and at night they run at 10%. It's using a Arduino Mega to provide 8 PWM channels to control the light levels of each segment though an LED driver module.
-Rob
How nice you thought about reducing the brightness, this can really be an issue in dim light or at night.
Our bus company here in Holland (Utrecht) only realized this after complaints about readability of their led signs.