Lotta great stuff on the mp3car website. The downside to an integrated unit is you can't take it out of the vehicle, but there are more options now.
The HDD is the weak point, it fails before everything else unless you dunk the whole mess in saltwater or have a lot of conductive dust in the air.
My senior project in college involved an autonomous robot, the thing had to drive itself over a variety of obstacles, so there was a three stage shock absorber plan...vehicle suspension, computer case suspension and HDD suspension.
In addition, the OS and all critical applications (nav, etc) ran on solid-state HDDs. Their storage capacity is not as great as spinning platters, but like my MPIO vs an iPod, it'll never ever skip. All secondary applications and data logging used a ruggedized spinning HDD. Each unit took up less space than a mini-keyboard, including depth, with peripherals attached as needed and locked down elsewhere--RS232 linked GPSR, thermal imaging and sonar--since they just plugged in to a port somewhere on each box (three, all linked, performing different tasks and as backup to each other).
If it's possible to mount a solid state main drive in your laptop, with a secondary spinning drive, it'll last a lot longer...but I don't know if MS's or Mac's pigs of operating systems will fit on one of those drives, they're usually not more than a couple gigs. It works perfect if you're running an -ix like we were, you can even diagnose a failing drive on the fly since everything's running from the solid states, or run almost worry-free storage if the spinning drives are striped.
It'll also last longer if you pop the case once in a while and clean out the dust...it insulates everything and causes massive overheating, which usually means forced or catastrophic reboots right when you're doing something processor-intensive.
An old roommate of mine had a job for a while repairing laptops. They're not difficult to pull apart, and he saw plenty of instances where a good cleaning solved the majority of lockups and reboots...of course if it's gone that far, it's going downhill anyway and parts need replacing, but a thorough cleaning does wonders.
None of that helps if you've dropped it, tho. That was the most common cause of malfunction he saw, the unit was dropped and broke something--screen, solder, boards, etc...not always possible to fix without buying a new unit.
-Sean
*edit* There is one thing I forgot. I don't know if anyone makes a suspended swingarm mount for a laptop, but it will work wonders if you can find/make one vs using a rigid mount. We looked at this but it would have meant more time in the machine shop that we didn't have. Something as simple as an arm supported by a gel pack or foam does the trick, the difficult part is matching the suspension to the weight of the suspended components. The foam used in "space mattresses" (find that stuff at any home decor store now) works great as it doesn't "bounce" back, same with gel. Elastomer is a poor choice since you need a damper and that greatly increases the complexity of your setup. IIRC we used foam, but our components were very light. There are some products available that are sort of like gel, but more solid like elastomer...a quick and simple way to do it could be to mount a lightweight setup on the end of a swingarm supported by one of those gel wrist supports meant to go with a mouse and keyboard.
Less than 1.4" thick, starting at 4.1lbs., the Satellite® U200/U205 has advanced protection beginning its lightweight, ultra-strong, magnesium alloy chassis. A special shock-absorbing design with airpocket cushioning and padding materials protects key components (HDD, LCD, inverter) and the chassis against excessive vibration. A spill resistant keyboard allows time to save and close your open files and turn off the machine."
