Thanks for the feedback, I know it's not everyones ideal setup but there is a small market out there for portable desktops (luggables). Those start out at about 5k for something with modern specs. A purpose built case for a luggable starts at about 2000. You get a case 14" lcd, keyboard, and an empty atx case. Laptops are fine most of the time for my work but occasionally you need something with an scsi card or an available ide channel to attach another hard drive, tape drive, etc. Data transfer can be very slow through pcmcia cards. In fact, if you ever plan on using a firewire device make sure you get a laptop with an onboard port. I've seen some numbers that suggest pcmcia firewire cards are around 7 times slower than onboard ports.
Thanks to everyone for the feedback