Mobile Oppression Palace

The Mobile Oppression Palace was a creation of the enslaved human race after the interplantary incident created by Dr. Zoidberg on Freedom Day in 3002. He sought sanctuary at the Decapodian Embassy. The Decapodians were so outraged, they sent a fleet of ships and enslaved all of Earth. Using mankind as slave labour, they managed to build the Mobile Oppression Palace, which was intended to replace the Decapodian warships as the Decapodian's means of enforcing their rule on Earth, since occupation forces were expensive.

The Planet Express crew attempted to use a heat seeking missile to destroy it, however all seemed lost when it was revealed the Mobile Oppression Palace was, like all Decapodian technology, cold-blooded, making the heat seeking missile useless. Fortunately Zoidberg had a change of heart, and set light to an Earth flag, throwing it at the Mobile Oppression Palace, causing the heat seeking missile to get a lock on it and destroy it. It's destruction resulted in Earth being liberated, since the Mobile Oppression Palace had been the Decapodian's sole means of enforcing their rule on Earth.

Trivia

 * The abbreviated name for the palace is MOP.