We bought an asus eee 901 with ssd a couple of years ago we took it on a small tour last year and its worked out well for us. I have installed ms mapoint (which I can use offline) and used pushpins to show all campsites and warmshower hosts on route. Even watched a film one rainy night.
Its quick, under a kg, battery life is great but even with a 16 gb sd I would love to have a bit more room.