HP
iPAQ 600 Series Business Navigator

This HP device was an unusual design as it provided a PDA-like experience but had a standard keypad which had a so-called smart touch wheel in the centre of the keypad. It used the Microsoft Windows Mobile 6.0 Professional operating system.  On its side it has a "jog dial" button to allow a user to easily scroll and select information. It was made by Taiwan-based Inventec Appliances.