Post having the signs idea with dyanamic signs, another thing that could be done might be dynamic archery targets. I know this can currently be done by a DM but maybe this could be done by players.

For instance, if I want to take the CDL on an archery training thing in the future, i could take five archer targets out of stores (inventory items) and place them on the floor in various places(ground target special power) creating a target on the floor to be shot at for the trainees.

A dialogue could set size of target, setting it's AC (if using creature type - providing it's in a non neutral npc faction) with things like:

Large - AC 15 Medium - AC 20 Small - AC 25

and setting the target's name accordingly with SetName.

The targets could replace in inventory with a device that lets them be removed again to save bob anybody walking off with them.

This could also be done with combat dummies too or "stuffed goblinlike bag" or something :)

I was also thinking of something like the wrestling animatrons that works between players too but I'll think more on this first.