Here's the original company: Ski Racks, Snowboard Racks, and Locks | Ski Key Systems
They work excellent but unfortunately the resort has to have the matching rack for them to work. As I mentioned this isn't a problem in Canada and it appears some parts of the states, but others may not have them.
I'm sure like any lock they can be defeated, but you'll be tougher to break than the thin cable lock, and they are smaller and lighter in your pocket. You'd have to remove a binding to get the board out, by that time they'll steal somebody elses...