On an English QWERTY keyboard, since they're slightly differen't from an American version.
(Mine doesn't have the accents for vowels as shown in blue, but has all the other blue things)
A few of the F# keys, depending on particular programs.
Caps Lock isn't often used for actually entering in capital letters. I often re-bind it in games.
The Insert, Home, and End keys are never used.
The Pause/Break key is never used.
I pretty much never use Alt Graphics.
I never use the right Windows Key.
I never use the Menu key.
I almost never use the key above Tab, as I have no idea what the characters are actually used for.
[ `¬¦
]Normally I don't use the Numpad for anything, other than sometimes quickly entering in numbers for passwords and similar things, so all of those are left alone.
I never use the Scroll Lock.
