I am considering buying a uMBP, either a 13 or 15" as a second computer to compliment my main machine, a Power Mac G5 tower. I do translation work, with MS word and excel, several dictionaries, a mail client app and a web browser open at the same time, copying text and info back and forth from app to app. In the past I used an iBook G4 14" for this and it was barely usable, so I am concerned about buying a 13". In terms of portability and even desk space, the 13" seems like the best choice, and it's cheaper, allowing for a bigger HD and 4GB of RAM. Anyone care to comment or give me their opinions on the usability of the 13" as described above based on their experience?