I always wonder and other people may agree. What is in your vehicle PC and setup looks like a long with map software(s) you are running.
Is that a question, I'm a little confused by the wording? Are you asking what people are using in their vehicles as a CarPC? And what software they are using?
If so, what I am using is an old "ruggedized" tablet made by a company called Xplore. They're pretty cool, magnesium case, mil-spec stuff. I designed a few of the touchscreens they use. It's accepts touchscreen or pen stylus input. Has anti glare and blah blah blah. It's pretty much everything I need, except the drive. I wish it were solid state. I built my mount pretty solid but I still get a little shaking when on the trail. It is built to take bumps and what not, but I still worry. If they ever make a retrofit drive to be solid state I will be all over it.
For software I use Oziexplorer on the trail and Streets and Trips for highway stuff. Ozi requires a bit of manual input to get stuff going. I had to download the geopdf topo maps and reference them. For sate imagery I pulled images down via googleozi. Mapped pretty much from Silverton to Ouray to Lake City. It took a while to do, but I had more time than money.
For mounting, I used a Ram Laptop mount base, pole and arm bracket. For the actual laptop mount I used the one that came with my Xplore tablet because it was built for that exact tablet. I also put an inverter, slot load dvd player and usb hub onto the mount as well. The base that mounts to the set bracket was something I fabbed up. It has two 12V sockets for accessory power and is tied to a 3rd battery that is isolated so to not drain the starting batteries. The terminals are properly shrink wrapped now =)
This setup worked great for our trip to the Colorado last year. I looked at a lot of different software and there is not one turnkey solution is pretty much what I came up with. A lot of them do something really well, but not quite everything. Hence my reason for having S&T and OE. Overland Navigator is pretty slick. All the maps are coded, satellite imagery available. Large buttons! This is useful if you are using a touchscreen. While the price for imagery may seem high, I spent a LOT of time downloading my own images, organizing them, loading them into Ozi and such. It was a good learning experience to do it all because it made me learn the software, but it's not as turnkey as ON.