1. Wiimote/ Wiimote & Nunchuk / Keyboard
2. Classic Controller / SNES Pad
3. NES Pad
4. Ye Olde Gravis Gamepad for the PC
5. Gamecube Pad
The Keyboard isn't the most immersive controller ever, but its sheer number of possible commands, functions, macros etc. and the lethal accuracy in almost every game type ever puts it at the first place. Honestly, a pad player has absolutely no chance in an FPS match against a keypad player with similar or even inferior skill.
As far as pads go (and I'm not really a pad person), I like the Classic Controller quite a bit. I have small hands, so the buttons are positioned and spaced very nicely for me, the analog sticks are good, the D-pad is good, and the shoulder pads are good as well. A solid pad which is only limited by its usability - since you can only use it on VC games or other games that make specific use of it, it's not as great as it could be.
NES and Gravis pads are there mainly for nostalgic reasons, though the Gravis pads were solid peces of hardware in their own right.
Oh, and for the record - the Dualshock blows.
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