A Complete Beginners Guide to the Arduino

Forum 2005-2010 (read only) General Frequently-Asked Questions
2

Can we take a look at your code?

First thing that came to my mind:

//PSEUDOCODE
all leds off
for 1 to NUM_OF_LEDS store the current iteration in i and do
  for all leds starting at i-1 do
    turn on 
    wait
    turn off
    wait
    increase index
  start at end and iterate over all leds until current iteration is equal to i
    turn on
    wait
    turn off
    wait
    decrease index

Obfuscated pseudo code :sunglasses: