A 10 60mmx60mm Led matrices controlled by an ATmega328 + 10 MAX7219 ic’s from Bajdi Electronics:
Made a big LED matrix this week using 10 60mmx60mm LED matrices. I designed the PCB’s myself and had them made in China. Every PCB has a MAX7219 and a header to plug the LED matrix in. The 10 PCB’s are connected together using jumpers. Writing code for the MAX7219 is really easy thanks to the fantastic Parola Arduino library.