The Zypad WR1100

If it was not because of the processor (ARM) I could have called  a Military UMPC. The Zypad can be worn in your wrist and is loaded with Linux and everything you need to survive in any conditions.

This bit of bling is a ruggedized wrist-worn personal computer designed for the bush. It contains a high performance CPU with 128MB of flash memory and 256MB of RAM.

You can find more information about it here.

Via Military Tech - CNET News