If you want an in-car tuning laptop, a netbook is probably a good idea. Good battery life, usually dont run very hot, small form factor (screen size is the downfall). Im a big fan of Asus, only run their motherboards in all my custom desktop builds and have only had 1 fail in ~10 builds, and that was back when there was a huge scandal over a 3rd party vendor supplying inferiod capacitors. 6mo out of warranty, Asus sent me a brand new mobo, I paid to ship it there and thats it. The eeePc's are great, I think you can get them up to 13" now too. Small screen for tuning, but I usually only make small changes on the fly and do most of the work at my desk (if I can help it).