This is cool project to pay attention to. It can be used for PC modding or elsewhere where scrolling text effects are needed. Display is built of 50×7 LEDs that is controlled by AVR AT90S2313 microcontroller (may be substituted by ATtiny2313).
Text can be sent from computer via RS232 port or displayed from external EEPROM 2k memory where 768 characters can be stored. Fonts set of 256 different characters can also be programmed and mast be written to EEPROM before sending text to display. Hardware project with 3mm LEDs can be downloaded here. And latest firmware here. There might be minor changes are needed to adapt to newer WinAVR and ATtiny2313 microcontroller.