The closest I've come to that recently is an old Casio BOSS SF-4900C digital organizer that I used while out hiking and walking. It worked great (I was getting

The closest I've come to that recently is an old Casio BOSS SF-4900C digital organizer that I used while out hiking and walking. It worked great (I was getting really annoyed at the lack of products for this application) but I used shorthand and didn't intend to transfer the data out at all. It was definitely easier to solve the problem as a whole using dictation or writing breaks every 20m or so. Some of the portable keyboards out there are looking really fun to play with, but they don't seem like they'd work well while walking. In the case of laying in bed, the best solution I've found is a lumbar support pillow for office chairs, a pillow with a flat back which I use as a table. It is comfortable, plush but firm, and makes a really awesome device platform, with friction to keep things from sliding around and also a mousepad-style texture. I use it more than my regular bed table and even took it on vacation...