Fun factoid: your voice will mirror your mental state and/or your physical state.
Secondary fun factoid: due to the body state thing, there’s no need to go all Method if you need to sound like a little… unhinged… Just find a physical state that makes the same vocal quality.
Which is to say that I just tracked vocals standing on one leg in a pair of teetering 6″ wedge platforms, randomly swinging my free leg around and almost falling over a couple times. But I got the sound I wanted without having to get all spazzed out.
And it probably counts as some sort of a core workout too.