Hi,
I'm also considering touch screen possibilities. For static Orbiters I think that LCD monitors with touch screen feature would be best option. But the problem is that one Pc could easily run one MD output to TV and one Orbiter (not MDs) X session on different video output, but currently Pluto won't allow that...
If you move around a lot, than option you already mentioned apply. (tablet pcs, PDAs or Mobiles )...
Regards,
Rob.