The spell is very cool but I was wondering what the general feel was about the ability to "Tag" a person within a certain radius (Sort of like the set ally mode) so that you can send them a message at a later time? Perhaps something like so long as it is during the same reset or a certain amount of time they are tagged?
Or even something like Scrying?
If it's a friend/henchman you can summon them with a personal message. If it's an enemy you can send anonymous menacing messages or threats upon swift winds and that sort of thing. The spell would still emit in a radius around them to allow eavesdroppers and such. Small-scale sendings are cool but just trying to think of ways to expand the spell's use since it is fairly overlooked it seems.
A flag a random location system works a lot better for a teleport spell instead of a magical messaging spell.
Cool idea, but, one point to make...
You don't always know where they are.
That would be Sending (//%22http://www.d20srd.org/srd/spells/sending.htm%22).