I think there can only be one possible winner of this highly coveted Scratch 'n Sniff Award..
I give you the evergreen Shackwacs..
The shock on entering the finest ergonomic slum known to aviation was topped only by that memorable first inhalation of the Shack's unique sensory cocktail - composed of oil of
fluide hydraulique, AVGAS, fragrant leather seating that had absorbed 30 years or more of tobacco smoke, sweat and vomit, with signature keynotes of Elsan fluid, forgotten offerings from the galley and ancient electric wiring.