Seperable mobile phone

The Separable Phone is a concept device from NTT docomo billed as the 'world's first handset that separates into two functional units'.

The detachable keypad can be put to multiple uses, such as a game controller, or as a remote control for the phone's camera or on-board projector. You can even use it to tap out your notes while chatting on the phone, for those 'multi-tasking yourself to death' moments.

Source: 26 August 2010