BockiMessageBoard is an open source library for Arduino to communicate with standard LED displays from Armplus. Supporting Europan characters, printing to several pages and setting animation of text.
Supported Amplus LED Display board http://www.amplus.com.hk/LED_%20AM03127-H13.htm
Circuit information http://arduino.sundh.com/2012/01/arduino-ethernet-shield-hooked-up-to-led-message-display/
Download the GitHub files and add them into your Arduino sketch folder, in the folder "libraries".
See the 'examples' subdirectory for usage examples.
There will be updates supporting more advanced LED screens in different sizes.