Cosigning on Mononoke (so, so damn hard!), Natsume's Book of Friends (Mushishi's kinder, gentler shonen cousin), and Cowboy Bebop, if by some chance you've not already seen that one, also Samurai Champloo. Kino no Tabi, perhaps? And the Black Lagoon anime is remarkably faithful to the manga and actually adds some excellent small characterization/backstory bits into transitional scenes, instead of going the too-common filler-episode route. The non-Mononoke arcs of Ayakashi are also fairly interesting -- one is, but for the framing bit at the end, a fairly straight retelling of "The Lantern Ghost of Oiwa".