This is a bit obscure but worth knowing about I suppose, perhaps it could be used as a "ghetto hearth".
1) Enter and exit an instance (and reset it) until you get a "you have entered too many instances recently" message.
2) Que for any random dungeon (I suppose a specific one would work aswell) and get an instant invite.
3) Take off all your gear and die. Then leave the group.
4) You'll be outside as a ghost. Run/fly back to the instance entrance and try to enter. It will res you with the ""you have entered too many instances recently" message outside the instance. But it hasn't teleported you back to where you originally qued from.
5) Give a thought to those poor scrub DPSers who waited around 20 minutes for you to do that, then fly off on your way!