Lets assume that "helpful" traps are permitted. Any discussion to the contrary is for another thread. I am however open to feedback on helpful trap creation. I basically see them as not traps, but immobile magic items (which makes them cheaper).
I was thinking about helpful "traps" to have around a house/lair/fortress of doom. Here are a few ideas I had.
Drench (wiz 0) Shower with no need for a drain/towels. As best I can tell the water doesnt persist. Could also accomplish a similar effect with Prestidigitation or Create water.
Mending (wiz 0) Insta-seamstress. Possibly for use as a business/ cover business. Trap wouldn't really be necessary, but you could make the trap and hire a peon to use it in your abselce. Constantly having to cast a cantrip would get tiring, but that's a discussion for another thread.
Magic Stone (Dru/Clr 1) Put a few of these around where undead are common. You just empowered the common folk to help destroy them. For this I imagine a plate where you put three stones and they are then empowered per the spell, rinse, repeat
Teleport stone (wiz5 I think), similar to a permanent teleportation circle, but can be made earlier and the end location can be changed for each person to use it.
Create food and water (CLr3), self explanatory
Unseen servant (wiz1), Step on the stone, give it directions and it will repeat that task for an hour. Could theoretically make a new Servant every round with new directions.
Endure elements (wiz 1) Saves you from having to cast it every day and youor entire party can use it. Hell, the entire town can use it. Make it proximity and anyone who gets within X feet is protected. Great for extreme environments (desert/Frozen tundra)
I have an idea to combine Aura of the Unremarkable with a teleport effect to quickly and easily distribute my army of thieves around the city without anyone noticing the fact that they seem to just appear all over the place. Of course they're on their own to get back.
Rally point trap would be interesing to use in combo with the teleport trap above. A small team could teleport away and back with a fair amount of ease. Edit: not rally point but the 6th level wizard one who's name escapes me.
What else ya got?
bump