NTT DoCoMo's modular phone takes an inexpensive handset unit and allows it to be slotted into different sleeves depending on your fancy.
Can't decide if you want a slider or candy bar? Wish your phone had a gamepad or QWERTY keypad? NTT DoCoMo's modular phone takes an inexpensive handset unit and allows it to be slotted into different sleeves depending on your fancy. More than just a fashion tweak, the different holders actually change the functionality of the mobile. This is a prototype model, so no further details were available besides a simple panel showcasing possibilities.
(Via Crave Asia)
Also be sure to check out more cool prototype phones here.