Pressure Gauge On Carbonated Beverages
Never get sticky again by exploding cans of cabonated drinks!
Just check the displayed pressure on the pressure gauge. The higer or lower the pressure in the can the higher and lower the liquid rises in the small plastic gauge next to a number that tells you the pressure of the contents.
You could locate the gauge anywhere on the can or bottle and in any convenient shape, so that it would be cheap to add. Most likely on the side, vertically attached at the bottom to the inside of the container of liquids. Great for some microwavable products too, where the pressure denotes the temperature.
Reward: To see how small and easily this might be applied.