I was working on my Picaxe 28x2 robot from http://letsmakerobots.com/ and I wanted lights and I needed more sensors. I had four input pins left. With the 28x2 you can make the pins anything that you need. I went back to electronics to find some answers. I looked up shift registers on http://www.jameco.com/ and I bought the latest CD74HC164 serial in parallel out. This is why I made Easy Lights. For two pins you get eight lights. Yes there is a little flicker. It is a shift register. Each time the lights change you have to shift in all eight lights. On slower systems you can use the Master Reset to clear the lights, but it still flickers when loading the lights.