I've got a 7" notebook which I think would be useful... Id have a ton of spare room in a 12"
I actually use one of the black square containers I got for $4 at crazy clarks... Its big enough for my lappy and a few ep's etc... keeps all the cables neat and tidy..
Whilst I was initially worried about its bulkyness, I found that for the drive to dark skies it doubles as a good box for cables, and random accessories like star charts/books etc.. makes it easy to find everything when i get to the location too.. .