Hi,
Here's a video of a reprapped fluidic logic circuit that I made recently:
www.youtube.com/watch?v=Fo85u9mnp9k
It was made with a RepRapPro Huxley. Each siphon has a transparent window glued to the front. The connecting conduits have no front - they are open channels. The insides of the siphons and the channels are coated with Rain-X AntiFog, which is hydrophilic.
Will