The local police placed this on our property this morning just for us! (People fly down our street, so it's probably really for them...) But, of course, we had to get in the car and drive by about 5 or 6 times just to see what it does.
Then we tried riding by on our bike... oh, yeah, it works that way, too!
Tomorrow, we might try running. The neighborhood kids figured out this evening that it works for skateboards, too.