Capcom Pad Soldier Controller (Super Nintendo)

It is an oddly-shaped six-button fighting controller, and one of three variants released by the two companies during the early 1990s (the others being the "Capcom Pad Soldier" for the SNES, and "REAL Pad Soldier" for the 3DO (the latter handled solely by ASCII)). 

The idea behind the design was that you could use three fingers for the 6 action buttons, much like an arcade stick, but the convenience of a gamepad. The left side is contoured so your hand can maintain a sturdy grip, and the buttons are off-set to reduce strain on your right wrist. You can still use your right thumb, and it feels very natural in your hands.