Have you ever had a dwarf commit such a heinous crime that he was to be executed? Are you getting tired of just criminals get hammered for executions? Do you want some other ways to get rid of useless and annoying nobles? What are some other Execution Ideas that you have developed other that locking the dwarf in their rooms or dropping them down a pit?
I've thought up of some sort of gallows.
Build a 2x3 tile floor 2 levels above the ground. Make stairs or ramps to the floor. Then build 2 pillars on 2 corners of one long side. Place a door in between the pillars. Build a floor extending another tile out from the door. Build a lever on one side of the door, and link it up to the door. Pull the lever to open the door. Then build a hatch cover on the side of the floor facing out from the door. Build another lever on the other side of the door. Link it up to the hatch cover. Then place a rope between the hatch cover and the door. your gallows are now complete. When you feel like executing somebody, open the door, assign the dwarf on death row to the rope, shut the door, assign the dwarf to a burrow on the hatch cover, and open the cover. Either the dwarf's neck will break, or he will strange to death eventually. Test this on a useless dwarf or annoying noble, and post the results here.
It should work, or else the rope will break under the dwarf's weight.