DF2012:Dwarven atom smasher
The Dwarven Atom Smasher is a nickname for a drawbridge in waste disposal or militarily-significant applications. It exploits the implementation of drawbridges to utterly destroy any objects and most creatures in its target area. A DAS works fine as a trash compactor to smash boulders, items, and fluids straight into oblivion.
 Smashing against the ground
In this design, a drawbridge is built to come down on at least one tile of solid ground. The drawbridge is raised, the targets are placed (or move of their own volition) into position on that ground, and then the drawbridge is lowered, erasing the targets from existence. Most commonly, a garbage dump activity zone is used in order to place items beneath the drawbridge (as stockpiles cannot be placed on top of existing buildings), but other methods such as flowing water have been used with varying degrees of success.
Sand or dye in bags doesn't get erased while the bag does, creating a small pile of sand or dye on the ground. Similarly, contaminants (eg blood, vomit) are not erased when a bridge descends on them.
 Smashing upon closing
In this design, a very compact drawbridge (as little as one tile long) is used, and the target area is the one-tile wide anchoring area, where the bridge will close. This often uses walls, locked doors, or other solid objects, leaving the targets nowhere to go. The drawbridge is lowered, the targets are placed (or move of their own volition) into position on the tile(s) that the drawbridge will occupy when closing, and then the drawbridge is raised, squashing the targets flat.
 Immune creatures
A DAS will not work on some tall creatures. Creatures with a size over 1,200,000 (e.g. elephants, bronze colossuses) will make it impossible to raise a drawbridge they are standing on as well as cause a drawbridge to immediately deconstruct if lowered upon the creature. See the list of creatures by adult size for a complete listing of creatures immune to bridges.