The other day someone asked my how an LCD projector worked compared to an LCD screen on your laptop. Their general impression was that the laptop screen was like a bunch of LEDs, so how could you "project" that? I didn't really know. I knew that it was backlit and that's why you could project it, but had no idea how it worked. I asked Kelly Flanagan and he didn't really know either, but he sent me this really good tutorial showing how it works--interactive and everything. Apparently this is just one in a whole collection called Einstien's Legacy.