I've figured out a new way of a trap...at least i think it is a new way, but anyways i got the idea when i was thinking about how i could make floors fall on a group of goblins climbing down a set of vortex stairs. then i remembered about the one comunity fort that raided traders instead of trading with them. so i basicly built a tower to test it out and used it on the dwarves that were there.
Step 1: dig out a vortex staircase so golbins have to walk 100 squares for a 10x10 trap
Step 2: build a tower above it and have a stone storage up there for quick rebuilding
Step 3: build a support 1 floor directly below where you will start building the inital trap position and link it to a lever
Step 4: build a 10x10 floor over your spiral staircase connected to the tower by bridges
Step 5: wait till all the goblins/creatures you want to kill are on the vortex staircase
Step 6: pull the lever and enjoy
Step 7: rebuilding is easy since that vortex staircase starts from where your dwarves are you can just build ramps back up to the top
note: any other enemies will be stuck outside till you rebuild it
another note: make sure there isn't a dwarf standing anywhere outside nearby the tower since it will knock them down.
first test video: http://mkv25.net/dfma/movie-480-hammertrap
second test:
http://mkv25.net/dfma/movie-481-shrapnel
[ April 01, 2008: Message edited by: etgfrog ]