Let there be light...

I recently bought a 3D printer. I'm not sure yet how much use it will actually see, so I went for a cheap model - one of the usual acrylic DIY kits shipped from the far east. While it's actually working rather well, there are a few details that are bothering me. For one thing - you can't see what's going on beneath the nozzle without a torch. However, using a 3D printer and some LEDs, resistors and some experimental circuit board, that problem was easily solved...