About a month ago I bought a Tablet PC (HP T1100). Mostly I wanted to see how it worked, play with the form factor and so on. Tuesday I'm flying to DC for and NSF Review panel. I have about 15 proposals to comment on before I get there and they're in PDF format. I thought "The tablet is the perfect form factor for working on an airplane, especially since all I have to do is read and comment on the documents." How natural it would be to view the PDF document and write notes on it. Unfortunately, it can't be done as far as I can tell. This floors me. The Tablet's been out for two years and you still can't do digital ink on PDF documents. Wow!