The Lowrance iWay 250c GPS system is an entry-level pocketable device.  It comes with a 3.5" touch screen display and is pre-loaded with maps of the US and Canada by NAVTEQ.  It can connect to your computer via USB and play music.

Sleek, Handy, Automotive GPS Portable with Multimedia Extras.  A Perfect Fit for Your Car, You Pocket, and Your Budget!