Spring Loaded Traps.
A trap that can be built into a room that will automatically hurt the next person who enters the room (not counting the person who made the trap). One time use, doing something like 10 damage for a small trap, 35 for a large one.
I think it would be a nice addition into the game, and seriously change some of the military strategy that has developed.
Once the trap has sprung, it is not usable any more (but can be deconstructed for some of the resources back).
I would think the traps attack should have the chance to be blocked based upon a persons skill in 'fighting'.
