One of the vendors we are planning on visiting while at CES is Black Diamond Advanced Technology, the makers of the SwitchBack Ultra-Mobile PC.
The SwitchBack is a rugged UMPC, with a built-in thumb keyboard, that also features something very unique: plug-in modules for the back of the UMPC. Here is a list of current modules available for the SwitchBack:
In addition to the Back Modules, the SwitchBack can run multiple operating systems independently or simulataneously: Windows XP, Windows CE, Windows Mobile, Linux, etc.
My contacts at BlackDiamond tell me that they will be in full scale production in Q1 2007. Contact Black Diamond and they will connect you with their resellers. The price of a basic unit with no modules will be approximately $3,600.