Sony's FES is smart watch that can last for two month on a single charge - using an E Ink display that is wrapped around the entire watch body. The watch comes with 24 designs that can be selected at the press of a button.

The FES watch will go on sale in Japan towards the end of 2015 for $240, pre-orders are available on some department stores.

E Ink display info: 
Flexible E Ink