Pen Computing Magazine
From the Pen Computing site:
Pen Computing and Rugged PC Review cover all aspects of mobile and rugged computing, including reviews of rugged and semi-rugged notebooks, Tablet PCs, slates, smartphones, handheld computers, Pocket PCs, pen computers, industrial handhelds, PDAs and other ruggedized computing equipment. Rugged PC Review also explains rugged computing standards and definitions.
At one time, Pen Computing Magazine was a bimonthly print journal focused on pen-based and mobile computing. If you are interested in alternatives to traditional keyboard input and related mobile technologies such as ruggedness and wireless, you've come to the right place. If you use or are considering using a pen-based notebook, pen slate, or handheld/PDA computer, we'll keep you up to date. We feature more in-depth coverage of individual pen platfoms than any other printed source.
Pen Computing Website