Self destruct

A selfdestruct is a system imbedded in a device, ship, or location designed to destroy it.

Wraith
The Wraith have selfdestruct systems built into their cruisers. These selfdestructs can only be overridden by a command code. It is presumed that Hive-ships and possibly transports have them as well.ATL: Submersion The Wraith carry also personal selfdestruct to prevent any questioning by the enemy. Wraith warriors have them imbedded in their armored chestplates, while commanders, scientist and other high ranking Wraith have them on a belt that they carry on their chest. ATL: Suspiscion Wraith darts selfdestruct by flying into something, such as the enemy's city. ATL: The Siege part 2

Ancients
The Ancient Aurora class vessel had a selfdestruct which was powerful enough to destroy two Wraith cruisers. ATL: Aurora

Atlantis
The Tau'ri designed a selfdestruct system for Atlantis to prevent it from falling in the Wraith's hands. The system consist out of naquadah generators that overload and a virus. The virus was designed to prevent the Wraith from accessing parts of the database out of the debry.