Singing unaccompanied I generally have no idea what key I am singing in. I usually run the tune through in my head to make sure I can reach the highest note, sometimes finding out too late that I was over-optimistic. Someone once pointed out that I was singing in tune with the freezer that was humming away in the corner.

I occasionally play Northumbrian smallpipes. Guitarists who pluck strings as they try to work out what key I'm playing are told, quite truthfully, that it's in F-off.