This thread (and also one earlier today on the OcUK forums) have all but persuaded me to put GPS on my carputer!
I'm going for
this 
Gonna have a nice touchscreen TFT in the dash, so something like this will be perfect, a nice small "mouse" along with voice directions!

Of course I shall have to do some playing to get that to use a seperate sound card to my music, and a seperate speaker (probably a slimline one in the headliner above the driver's seat) as i don't want music blasting loud when suddenly in the middle of a guitar solo i get "
IN 100 METRES TAKE THE THIRD EXIT ON THE ROUNDABOUT" scaring the schit out of me!!
Damn i knew browsing AT would cause me to spend lots of money one day, and i thought i was doing so well removing HD and FS/T from my list (not that they would help anyway with me being in the UK)
I have an iPAQ PDA, but it's going to work out more expensive to get one for that, plus a storage card, than it is for the USB one and software
Confused