I have issues with Polyjuice!Moody. So, right, Crouch Jr. keep him in trunk so he can harvest hairs for the potion, so why doesn't he change into ill and underweight Moody? Does the potion pick the optimum appearance for the drinker, let them choose or something? Why does the potion not change Crouch Jr. to look like Moody as he was at the time the hair was plucked?

I suppose this extends into hypothetical questions like: if you drank Polyjuice containing the hair of a dead person what you would come out looking like? The living person or a pile of bones and stuff? If the latter, couldn't we use it to see if Sirius is really dead or not?
And yes, everything does come back to Sirius. *g*