This project uses a 32X32 LED array (1024 LEDs in total) and a beagle bone black board. The page describing the project has very nice explanations on how the whole system works (and LED displays in general).
Blinkenschild is a portable sign consisting of 960 RGB LEDs. The images/movies to be displayed are stored in a SD card in a Teensy3 board and controlled via bluetooth. Resolution is not as high as LCD monitors but the refresh rate is much higher: