In all seriousness get a laptop that will give you the best battery life. ...Everything else is secondary ... The company I work for has literally bought tens of thousands of PC's over the past 20 years. ...
Thought I'd leave this for those who find this thread in the future, as everything else is NOT secondary when the machines die. Batteries are indeed vital, but motorcycles are very hard on computers and our work group is REAL experienced at - ahem - aggravated environmental testing. Want to know what survives bumping around in a backpack during a week of swamp time in Cameroon or on the side of a cliff in Greece? Our real world Gummint-funded torture test experience has been that:
Dells are ok for the office and conference rooms and while we do regularly go through them, the IT group buys them for us by the bunch at a real good contract price, plus you can get parts and fixed anywhere in the world. Literally. The various Dell refurb laptops and desktops we've bought on our own buck for kids computers have been quite reliable, even at college. The kids have found that even when they do something physically stupid, they can generally find cheap parts and somebody who has fixed worse. Leading to the later story: "Yeah Dad we were sitting on the judging stand at the arena and after it bounced down the stairwell, then we used a cake knife to replace the hard drive..."
Panasonic and HP's ruggedized laptops worked but generally seem to run a generation behind, cost a BUNCH more, and get left behind because they are like a ton of bricks in a backpack. Nice machines but budget busters and you can't use what you don't carry along.
HP's regular laptops haven't been any better or worse than the Dells work-wise for some folks we've worked with, but in college use, our little parent collective thinks that they fail a little more often and it's a pain to clean out the bloatware.
The worst have been everything we've gotten from Sony. Girls LOVE the looks. We bought them for the features and using their products is great while they work, but they're not made for our environment. We've killed every camera and laptop we've gotten. Well, a Columbian Army jeep did run over the last laptop, but that's another story.
On the upside and for outdoor/travel use, most of the netbooks have been really hard to beat, so much so that many of our field guys have bought them on their own buck. Bootup time of 25 seconds to back up field photos, place captions, and type notes on a work break. Newer ones have built-in aircards. If you keep them in a ty-wrapped plastic bag with some paper towels they work in the rain (laptops are too big), batteries can go 6-8 hours on an airplane ride (my Dell laptop sure can't), not too big for a seatback tray, and when they die (rarely) you just throw the thumb-stick in another one for cheap. Downsides are the external DVD drives, slower use of Powerpoint and other memory/processor intensive use, and smaller screens/keyboards.
I think tablets are up & coming, once we get past some hurdles. The touch screens are only good for a limited life, we need to figure out how to protect the screens for that amount of time, and the guys who tried the last generation for us said they were tempermental with weather.