Anon-X,
I've done a lot of research on this subject and have met up with those who put laptops on flightdecks on a large scale - Southwest, JetBlue Etc. I can also provide you with some useful information regarding JAA issues, charging, document formatting and electronic forms Etc.
Some go for the ruggedised expensive stuff, others standard business systems. All have gained very valuable (and expensive) experience you can gain from.
Feel free to write to me at the Towers and we can arrange a chat over the phone.