I think ViewSonic tried something like this a few years ago, if memory serves (saw some in the local Fry's). I don't think they found a market that worked for them, though. It was right about the time the first Tablets hit the street, though, so they may have been washed out by the flood of folks looking for tablets, and ignoring them once they realized that these devices weren't tablets (I think that was my reaction, actually).
