The Command Module is a device that Plankton made to impress Karen, and to try to replace her. The module has only been seen in the episode, "Komputer Overload."
The Command Module is an old dark blue hair dryer with an antenna taped to the back of a miniature light brown windmill with sharp blades, that spin very fast. The hairdryer on it has a built-in flame-thrower.
The Module disliked other robots and attempted to demolish them, but later, the robots combine into one robotic mayhem machine for Plankton to control, with the Module in the top section. At the end, since the giant robot is connected to a plug and eventually came closer to the Krusty Krab, the plug came off, thus, the robot toppled and fell, leaving Command Module and the others destroyed, ending Plankton's evil plan to steal the formula.
The hair dryer should have fallen off, since it was only taped, and would be much heavier.