Have you ever got into your car and left your mug on your roof or hood? We all have. 

 It's not until we're driving and others are beeping and waving their arms to warn us or at the stop sign (if its held on that long) when the mug falls and spills all over the hood that we realize. 

 We tested this out with Mighty Mug with professional stunt driver on a closed course. Check it out and don't try this at home.