we carry an EEpc of Asus with us, beefed up with a 500GB harddrive and 2GB of ram. Using it to prepare website updates, and it can just (but only just...) handle HD video-editing for youtube-uploads. (be aware, you need 1025x768 resolution for this mostly!)
I wouldn't want to travel without it, as it has 200GB of movies on and that is nice if you camp and it is dark 12 hours a day.
We can charge it on the bike (the asus uses a 12V input, which makes the chargers cheap) and be aware: buy a 12V charger which can not handle 24volts too. If the can handle both, the voltage drop in the charger is bigger (more electronics) and this resulted in a charger which only worked with the engine running. The 'only-12-volt' one we have can handle 2 to 3 full laptop charges on a parked bike.... although we had to pushstart the bike 3 times on the trip now after watching too many movies :-P.
Contact with family: skype rocks!
We also make backups via internet, and in 14 months, 47.000km's Canada to Argentina, we managed to upload ALL our movies and pictures... 65GB in total via Dropbox, really nice and for free. You do need a good friend in your home country who is online a lot to download all the stuff you've uploaded.
Friends of ours have lost ALL their pictures... so please, MAKE BACKUPS to your home country or something as often as possible