I told this story in the other thread, but here it is again for posterity.
BadBrick and I made a trip to visit Marco and brought some sheets of glass back. We had them laying flat in my wife's van, with the backseats out. They were in cardboard and strapped from side to side.
On the highway I had to slam on the brakes for some traffic and one of the sheets slid forward from it's cardboard taco and slammed into the drivers seat I was in. It exploded and showered me with glass.
I had to sit in the glass "puddle" for about 10 minutes while traffic moved enough for us to get to an exit and check everything out.