The Warrior USB Joypad has to be one of the scariest and coolest game controllers ever. Decked out like a mean looking Japanese warrior with a skull for a face, this joystick looks like a regular Playstation controller put on a Halloween costume. He even comes with his own removable mask. In fact it is compatible with USB, PlayStation PS3 and PS2. Check out the backside:
The coolest part of this controller is the freaky green LED eyes that light up. Besides just looking like he would scare the crap out of young kids, this controller also has functionality: a highly responsive button configuration, it supports vibration feedback with compatible games and you can switch between digital and analogue controls. It costs $25.