Due to the adventure modules The Sunless Citadel and Heart of Nightfang Spire, I really like what are technically traditional dungeons, in the sense that they descend, but both start at the top of towers and work down. It just has a separate visceral feel to the descent into adventure.
My absolute favorite dungeon type and location rolled into one, however, is a ruined city in the desert. I've only utilized it once in an rpg, but there are lots of movies and such out there that present the type of location I'm talking about.
Cellars, basements, tombs, and sewers can all serve to allow dungeon levels and sublevels, and the dryness of the whole location can really create a nice change of scenery for a campaign usually mired in moldy, dank dungeons adventurers are used to.