Hello,
I begin with my brand new Arduino 2009, and I have a question:
If I want to drive 120 leds ( only 5 simultaneously); is there any easier way than multiplexing?
I'm afraid multiplexing is too complicate for my level!
Thank you for your advice!
In theory, I suppose you could do 120 LEDs with charlieplexing and 12 I/O pins.
Otherwise, you could do it with fifteen 8 bit shift registers.
Many thanks for your answer, I will investigate, hoping Charlie Plexing
is a cooperative fellow! 
.... or you could use a MAX6594, that will drive up to 128 LEDs. Yes it is a charilplexed design but it is all done in the hardware so there is no programming overhead.
Cool, I will try this MAX 6594, it seems more accessible for me!
thanks to you all again