http://www.youtube.com/watch?v=2ZvoitbUNIw

http://www.hmsmotorsport.com/store/racing-...t-helmet-system

Ambulances and ER's could use this, IF riders had it in their helmets.

That is a pretty cool gizmo. I personnally like a tight helmet. Street riding conditioned me to wearing a tight helmet as they tend to begin trying to lift off your head when you get up into the high speeds (>80 MPH). I found that a size smaller than snug was still comfortably snug at higher speeds. It just carried over to my off road helmet although I think the foam is getting a bit compressed as it is getting a bit wobbly. Either that or my head is shrinking.