The things are heavy, expensive and are usually controlled by some kind of weird trigger controller. On top of that, maybe you'd find it hard to part with your trusty old longboard anyway? German startup Mellow is looking to make the upgrade a little more palatable with an attachable electric drive that can be mounted to any existing board and give it a little more zip.

The majority of electric skateboards available today rely on an electric motor to turn the wheels via a belt drive. Manufacturers are doing their best to hide these bulky motors and the batteries that power them to stop them getting in the way. In the case of makers like Evolve and the long-awaited Marbel board, this has even seen electronics built into the deck. 

But the Mellow team has engineered what it considers a pretty innovative way to set its wheels in motion – two motors are built into the 79 mm (3.11 in) wheels. These were developed in Germany under the watchful eye of Mellow co-founder Kilian, formerly an electrical engineer at BMW, and the team claims they are very quiet, highly powerful and tightly sealed to fend off troublesome water and dust.