If a magus is standing in a room and casts a room target spell, what range does that spell need.
I'm thinking touch, since by definition he is touching the room by being in it. But then would that require him to actually touch with his hand the walls, floor or ceiling?
Obviously the magus could not use range personal since he isn't a room and equally obviously range voice would be fine.
The advantage of voice over touch of course is that you could cast spells into a room from outside it, even at a distance.
"The range of a spell is the distance to the nearest part of the target of the spell" p.111
So if the rules, allowed it, the range would be personal. However, range personal stipulates "The spell only affects the casting magus... thus the target is never larger than individual." p.111
I think that if a magus in my game wanted to try for a minor breakthrough they could develop a range equivalent to personal that could only target the room in which the caster was standing.
Not necessarily although that is generally the way to effect those within a Room Target. Another way would be to first cast Opening the Intangible Tunnel with ReVi (page 162, ARM5:CR) and cast spells with Room Target through the tunnel.
The only caveat to the latter being that any magus in the room targetted could cast spells back at you through the same tunnel without having to maintain the concentration on the tunnel (as does the tunnel's caster).
Create and enchanted device to cast the tunnel for you and maintain concentration and you'll be free to cast all the Room spells you wish without any penalties or concentration checks.
Then this new range could be called "Centered" to affect a Target: Room centered on the caster. It should be same magintude as Personal, otherwise it would make no difference whether it was Touch or Centered.
Regarding "Prying Eyes"
This could just be a cosmetic or flavour thing for this spell. If the range is to the nearest part of the target, and you're stading in a room, it would have to be a very small room if the floor wasn't closer to you than a wall, since you're standing on it (hopefully). But does it matter whather yoy touch with your hand or with something else? I believe a Talisman is good enough to touch with, but does standing count? SOmeone mentiones that you'd have to stand barefoot, but does touch not count if you're wearing gloves or have really filthy hands?
The point about the comment in Prying Eyes is that you don't need an Arcane Connection to see the (unsensed) things inside the room if you can touch the external wall.
If you're actually inside the room, it's a pretty useless spell. So the description is assuming that you are outside, and that, therefore, the nearest part of the room is the wall.
I would definately allow 'touch with boots' to function for the touch range. Just image someone casting a nice "painfull memories" Mentem spell by kicking the sensitive parts.
For the fans of Avatar: the earth bending way for Terram magi is very stylish, so I'd give it a +1 to casting total if you affect the floor while walking barefooted. (much like a +1 for using a loud voice / huge gestures)
Opening the Intangible Tunnel allows you to target spells at the target of OIT. A person inside the room isn't the room, as the item inside the room isn't the room.
Note however that you can have an AC to a room, and therefore you can cast OIT targeted at the room itself, and thus target it through the tunnel.
EDIT: adding for completeness.
The Ear for Distant Voices and Summoning the Distant Images are two spells that let you use T:Room if you have an AC to a person or object inside the room. That's the only exception I can think of. They don't conform with usual targeting rules, however.
Take a look at HP p.79 What is an Intangible Tunnel Effect:
It is possible to cast spells through the tunnel that affect the Room, Structure, or Boundary that the target is in, as touching a thing in a Room, Structure, or Boundary is sufficient to affect the entire Room, Structure, or Boundary.