Ok, up here in the "northern" great white north, just about everybody has at least one.
I remember my first time crossing open water...it was about a 50' stretch...I was a bit paranoid (lake was 130' deep at this part), but I went for it, and successfully made it (barely, I slowed a bit approaching the oncoming ice and she dipped pretty bad)
But check this out...these guys are insane!
http://www.youtube.com/watch?v=c57RYaL7YT0