So, where from here:
WebNav: UI to see maps, nav stuff, that kind of thing.
CockpitCam: Now, everyone can ride the jumpseat!
Open LAN: Totally open LAN amongst passengers - play multiuser games, swap files etc.
'Online Traveller': Fill out immigration forms, customs forms etc (bit tricky cos' of lack of digital signatures standards, but eventually)
Any more?
There must be loads of neat things beyond the first step of giving people web access.