Wordclock is a project of clock where time is litteraly written.
I create a circuit based on ATMega328 (the same as you can find in most arduino), and TPIC6B595 shift register.
I use (and discover) multiplexing to drive the led matrix. Anode are directly drive by arduino (not the best method) and cathode by shift register.
The clock contains a ds1307 chip and a hc05 module for bluetooth communication.