While the majority Atari 2600 users stuck with the standard, stiff joysticks, the most militant opted for the Terminator Grenade controller.
Despite its unique, burly look, the Terminator was actually a standard, 9-pin controller that supported a variety of systems (including C64 and Vic-20). Today, it's both a fairly rare collectible and the only joystick that we wouldn't recommend carrying through airport security.
Looking back, I swear that I played with one of these controllers as a kid, but then again, it's just as likely the thing was a real grenade. [flickr via technabob]