Disclaimer: I don't really know anything about this sign, I saw it posted in Engadget and thought it would be a great alternative or addition, if someone could hack it to work.
http://usb.brando.com.hk/prod_detail.php?prod_id=00575
Nick
http://usb.brando.com.hk/prod_detail.php?prod_id=00575
Nick
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