I know these have been around for a while but I was curious if anyone has installed one in a passenger pillion. Maybe just use a plug in the wiring for when you want to remove the passenger pillion. http://www.viberider.com/
They did a demo at OC bike week a couple years ago. After yelling at the guy that it was in the back three of us girls ( who all ride thier own) got on for a few minutes. The thing is funny. I can't imagine someone putting on thier bike. But the demos have entertainment value.