Some Inventions are simply better left uninvented:

Black highlighter

Waterproof tea bags

Braille driving manual

Dehydrated water

Screen door on a submarine

Helicopter ejection seat

Air conditioning for motorcycle

Left handed pencil

Wooden barbecue

Glow-in-the-dark sun dial

Gasoline fire extinguisher

Battery-powered battery charger

Clear correction fluid

Fake rhinestones

Fireproof matches

Glow-in-the-dark sunglasses

Mesh umbrella

Solar-powered flashlight