Blinking 8 leds with the Arduino microcontroller board

I put on YouTube a short video that I made of the breadboard and the Arduino, with 8 leds blinking in a sequence.
The C code for that sketch is here : http://ardx.org/src/circ/CIRC02-code.txt
It is a very easy exercise but also where one can start writing his own programs, for instance to try to modify the sequence of the blinking lights.