However, the Queen has decided not to give permission for a change of colour for her official London residence.

BBC: Queen answers Irish bid to turn Buckingham Palace green

He said that they thought it was the first time in the company's history that there had been a permanent change to the colour of the post boxes.

BBC: Gold Olympic post boxes to keep sheen

Irvine is a planned community where you cannot change the colour of your door without getting permission.

ECONOMIST: California

At this stage, however, using the protein that way could turn reading into a truly electrifying experience: a charge of about 4, 000 volts is needed to trigger the colour change.

ECONOMIST: Showing off

For example, it is offering a service to mobile-phone companies in which subscribers can go online to change the shape, colour and other features of the case of their new phone.

ECONOMIST: 3D printing