Palm founder Jeff Hawkins today unveiled what he billed as a revolutionary new device in mobile computing. It wasn’t new Treo, though. It was a full-screened tablet computer, designed to be a mobile companion to its Treo line.

Called the Foleo, the Linux-powered device synchs directly to a Windows or Palm OS Treo through Bluetooth, uploading the device’s e-mail and surfing the Web. If the Treo is unavailable, the Foleo has Wi-Fi connectivity allowing it to find its own way onto the Internet. Basically it performs all the functions of the Treo, except in a more comfortable format, displaying content on a 10-inch screen and giving the user a full keyboard he or she can type on with all fingers instead of thumbs.

Palm has embraced the concept of the smartphone, focusing on its Treo line, so the larger format mobile computer might appear to be a change in strategy. But Hawkins, at the device’s unveiling today, said the Foleo fits in perfectly with a smartphone strategy. As smartphones become smaller and smaller they become more difficult to perform many of their designated tasks on. A companion device like the Foleo allows a user to handle bulkier or more interface-oriented chores like answering e-mail, editing documents or surfing the net on a larger screen and keyboard, while using the smartphone for more passive, such as viewing e-mail or navigation.

Though it wasn’t stated at the press conference, the Foleo gives Palm a reason to overhaul the old Treo design, which while functional is considered rather clunky compared to devices launched with the Microsoft, RIM and Symbian operating systems.