[7.12.12] Seriously?! -- Vinegar works as a wood stain when you add a metal object in the mix and let it sit in a glass container for a week. A handful of pre 1970 pennies will produce a beautiful pale Caribbean blue stain. A wad of steel wool will give you a rich reddish hue. A combination of tea and a metal object in vinegar will produce a black stain. Log this away for later.