You build it, and link a teleporter to it. It automatically starts building the pod that your Commander spawns in, much like the Nuke silo's behavior. It can hold several units. Send the units through the teleporter, and once the unit capacity is reached or it is manually fired, the units are shot out in the pod, damaging units and buildings around them and unfurling the into a battle. Now that I think of it, uber might not put it in, but please, someone mod this
Yeah soo drop pods...why don't we just make the Unit cannon so we launch said drop pods from planet to planet?