I've never brought a laptop on a tour, I usually just stop at libraries when I need a computer. So that's one options.
Although I'm not sure how that would work out with the pictures.
Another option you could consider would be a netbook instead. They seem like they are a lot smaller and more suited than a laptop would be for travel.
Again, no experience on this, but I've considered it a bit too, and may look into a netbook in more detail for myself...