The Mio devices (
http://www.mio.com/us/), are extremely versatile. I own two myself, both C320 units. The Mio GPS units have a SD card slot and have the capability of being "unlocked". Once unlocked, the Mio can be instructed to run almost any Windows CE 5.0 software. Some software suites have been created that will turn the Mio into a fully-functional PDA, along with traditional GPS capabilities. One of these is MioPocket. The latest version of MioPocket is 2.0 and can be seen here (
http://www.youtube.com/watch?v=LcWxGlfVAPM&feature=related).
From a forensic standpoint, I'm interested in the information left behind on the internal memory of the device. I'm also interested in the information written to the SD card during the operation of MioPocket. For example, a person storing material would be able to keep everything on an SD card and use the Mio as a tiny laptop. During a search, would an investigator be able to confirm that the Mio was used in conjuction with something like MioPocket?
Hopefully soon i'll have some additional information. It's something to consider, especially since these GPS's can be used for so much more outside of their design.