As mobile phone manufacturers experiment with yet more designs the latest craziness comes from Siemens in the guise of a pen. The world's first ever tri-band mobile phone housed in a pen - lets face it not that hard - offers all the standard features of a phone but in a pen.

The PenPhone, which is just 140mm long, can recognise handwriting written on almost any surface, and then use the information to dial numbers or write text messages. Even if no writing surface is available, you can use built-in voice recognition to activate the phone.

Additional features include an integrated loudspeaker and handsfree function. Using the PenPhone's Bluetooth interface, you can also connect wirelessly to your PDA or headset.