The cutting edge of bungee cords!

http://www.foxnews.com/us/2017/11/01/mom-strapped-son-to-roof-minivan-to-hold-down-plastic-pool-complaint-says.html

http://nypost.com/2017/10/31/mom-arrested-for-letting-son-ride-on-car-roof-thought-it-was-ok/