Very cool. The protons (H nuclei) actually jump between molecules to carry charge.
Water and ice are amazing things. Both are essentially black in the thermal IR, which can be handy.
Now that's an interesting idea. Ice is a pretty good insulator, but I don't know if some doped ice allotrope can be a semiconductor. It wouldn't be real hard to try some cases. You could make a diode or a transistor by changing water or vapor impurities while freezing a layer onto a surface.
John