We have designed a very cool expandable display based on Arduino. The ClockTHREEjr (8x16 mono) boards can be stacked side-by-side to make long LED displays, each one can display two 6" characters. Please have a look at or just launched KickStarter project. We need $2500 to purchase the min quantity of kits.
http://www.kickstarter.com/projects/252714519/clockthree-jr
Justin
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