Coming from Minnesota Originally, I can tell you just about anythign you could ever want to know about how to get around on snow and ice [8D]

We used to race quads and bikes on the ice. What worked exceptionally well, was to have a spare set of Knobby Tires (usally a semi-worn set that wasn't much good for the dirt anymore) and run hex head sheet metal screws into the knobs (short enough ones that they didn't puncture the tubes of course). The knobs on RC tires as too small for this, but imagine the traction of sheet metal screws run from the INSIDE of the, witht he points sticking out. When they wear down, unscrew them and put in a new set of screws.

This won't help for snow, but for ice, I can't imagine anything better. I gree that some sand paddles would be the go for snow.