Okay, so I have my ipod in the car and it works great and sounds great through the AUX port in my non-navi HCH.
The
'but' here is that I'd like to have:
a) more storage space than the 8GB on the ipod,
b) have more flexibility than just the ipod,
c) the ability to listen to something different than what my daughter is listening to in the backseat,
d) have something that I can later connect to an LCD screen,
e) and most importantly not cost a small fortune, hence I'm not buying an 80 GB ipod!
I figured an external USB Hard Drive (HDD) enclosure with built-in media player would be the best solution. I have an 80 GB hard drive available, so why not? I can later expand it to a bigger hard drive, if I want, since I have the
magic screwdriver. 
So, today I ordered one of these:
http://www.amazon.com/dp/B001876HMO?smid=A1CUXCEWGAZ8O2
I actually ordered it directly from geeks.com to save $5.
I will use the remote to control it.
Does anyone else have a HDD set up in their HCH? Any advice on where to install it? Other ideas?