We officially have "water on the moon" so let's have some lunar
boating ideas. Only problem, it is basically some ice crystals mixed
with dust, not even good for ice boating. However, I still think that
lunar lava tubes might have lots of ice and other volatile materials.
Lava contains lots of dissolved water vapor. When it cools, the water
may come out of solution and freeze in the lava tube where there would
be no air movement to cause it to heat up. So, maybe kayaking with
runners on the bottom in lunar lava tubes. Could combine my three
interests, caves, boating and space.