The best inventions solve everyday problems efficiently and with style. But some creations are much stranger. They either solve problems that barely exist or do so in wonderfully odd ways.
Consider Necomimi, a pair of cat ears controlled by the wearer's brain waves. First demonstrated in Japan in 2011, the ears perk up when the user concentrates and drop when the user relaxes. Despite their unusual appearance, they remain popular among cosplayers.
Then there was the Dynasphere, a giant one-wheel vehicle that could travel at 48 km/h using a petrol engine or an experimental electric motor. At three meters tall, however, it was difficult to steer. It was also prone to "gerbiling": sudden braking or acceleration could send the driver spinning around inside like a gerbil in a wheel.
In the 1960s, tyre company Goodyear experimented with illuminated tyres made from synthetic rubber. Bulbs inside the wheels made them glow in the dark. Unfortunately, the tyres performed poorly on wet roads and could melt under heavy braking, so the idea was abandoned.
Japanese inventor Kenji Kawakami coined the term "Chindogu," meaning "weird tools." He has created hundreds of impractical but strangely useful objects, including tiny umbrellas for shoes. His "Hayfever Hat" continuously supplies paper to someone who cannot stop sneezing. It is not elegant, but it does address the problem.
The Hamblin glasses offered a less dramatic solution to another minor inconvenience: reading while lying down. A system of mirrors, similar to a periscope, allowed the wearer to read at a 45-degree angle without lifting their head.
For office workers in need of rest, Ostrichpillow created a large napping pillow that cushions the head while blocking light and noise. It may make sleeping at a desk more comfortable, although nearby coworkers might not appreciate the snoring.
Inspired by submarine cars in films, German company Rinspeed built the sQuba, an electric sports car that could travel underwater. It could dive to a depth of 10 meters and reach 3 km/h below the surface, but it never moved beyond the prototype stage.
Long before digital pets, Americans briefly fell in love with the Pet Rock. Each ordinary stone came with bedding, a ventilated carrier and instructions for its care. It became a bestselling toy, but the excitement lasted only a few months. Sales declined, and production ended in 1976.
Perhaps the strangest creation is artist Dominic Wilcox's Crane Head Cereal Serving Device. Worn on the head, this milk-powered crane uses plungers to move cereal from a box into a bowl before firing in the milk.
For some mysterious reason, it has yet to reach the shops.