Movies Spoofed by the Postal Video Game Series

In Postal 2, the pet store advertises Sumatran Rat-Monkeys for sale.

When the zombies overrun the church in Postal: Paradise Lost, the Postal Dude says "I'm running this monkey farm now."

The local hotel in Postal 2 is called the Bates Hotel.

"Bring out the gimp!"
Basically the whole gimp and rednecks subplot.

In Postal: Paradise Lost, the bandit leader Two-Ears says, referring to his giant machine gun, "Say 'ello to my big dick!"

In the prison in Postal 2, there is a maximum security cell called the "Anthony Hopkins Suite". Curiously, the Postal Dude seems to have no problem escaping from said cell.

In Postal: Paradise Lost, there is a snowman centipede.