It's a sad fact of life that people entering prison often attempt to smuggle cellphones in with them by hiding them, um, internally. And I'm not talking hamster-like cheek pouches. This practise was not begun until well past the 80s (think Motorola brick phone; think "not enough KY in the world"), but even with the latest strides in miniaturisation it's still something of a squeeze to fit the latest handset up when you're going down.
Convicts can say a silent prayer of thanks to the designers of the Xun Chi 138, which at 2.64 inches long and under 2oz in weight is a far easier phone to conceal. Sadly they'll have to pass up on a few features most mobiles take for granted - Bluetooth, memory card expansion and a keypad have all been left out. Still, the tick-list is still impressively full, with a 1.3megapixel camera (that apparently only takes VGA shots), GPRS, mp3 player and - via a touchscreen - handwriting recognition.
Unlikely to reach anywhere outside of Asia, sadly.