Oud 27 is great, but very peculiar - it's a superdirty musk that settles into an elegant woody later.
Equally expensive, another dark musk, but more elegant and socially acceptable, is Kurkdjian's Absolue pour le soir. For the dirt part only, Muscs Koublai Khan by Serge Lutens. Something between dirty and clean, Musc Samarkand by Les Nereides. And for a fun, musky-leathery vanillic concoction, Dzing! by l'Artisan Parfumeur.