here is mine.
I use a PDA for navigation because depending of the country and the maps available, I use Tomtom, IGo or OZI software.
The problem is that the PDA is not waterproof and has no 12V supply. So I put it in a RAMTECH box, and included a Bvat-> USB power supply home made.
The king size model of RAMTECH fits perfectly the windscreen of 640Adv!
I wanted first to use a RAMTECH system to hold it to the KTM support, but it was too heavy an too big, so I made my own support.
I come back from Mongolia, and everything has been fine (at least with the dashboard)
I use also the PDA and MP3 player (not while driving, but in the camp)