Taz,
For some more ideas you may want to look at the Panasonic Toughbook. They use a gel pack mounted hard drive. The ruggedized units we used in police cars have a nearly unbreakable screen and super rugged case. The laptop could be dropped on concrete from 6 or 8’ feet while running and not have a problem. You might be able to use some of the components.
http://www.panasonic.com/business/toughbook/home.asp
Hitachi makes a 6 and 8 GB micro drive if you want removable media that can work into a usb reader to transfer data. They are working on 10, 12 and 14 GB versions.
http://www.hitachigst.com/portal/site/en/?epi_menuItemI...6934ab937c27aac4f0a0
I use an 8GB in my iPAQ and it works great.
This is were I bought my microdrive.
http://www.mobileplanet.com/us/product.asp?code=121717
Keep me posted on both your systems. I was going to start looking for a vehicle mounted computer to integrate with my Ham radio to handle packet transmissions. I use a Panasonic Toughbook for my portable radio system. The iPAQ would work but the screen is so small. The Toughbook has a great daylight screen with touchscreen built in and it is tough.
Keep me on the list. Price is not important, I need quality.