Yes, I also agree with Bose and IO.
Take one of these ultra portables with you (I use a FS lifebook which is excellent) or even a PocketPc (which does much the same job and is even more compact).
I would only add that if all else fails the chaps at Heathrow FP are brilliant - they will accept a verbal VFR FP both outbound and inbound and they are 100% reliable.