Designed by the French designer, Clement Logereau, the Nokia Unik is a concept phone that is made up of 152 small squares to add to the back of the Nokia Unik. Squares of metal, rubber, and transparent can be used as well as different colors. The squares can be bought from the Nokia Stores once the handset has been purchased.
Depending on your mood or personality, you can add and change the squares to give you a different texture to your phone.
via: Nokia Unik Cellphone Changes Texture With Your Mood - The Design blog