Dungeonpunk is a form of Setting Aesthetics popularized on /tg/ by Dungeons & Dragons, and is essentially a melding of Heroic Fantasy with Steampunk, Dieselpunk, Noir or even Cyberpunk by way of Magitek. Our frenemies over on TVTropes argue that a proper Dungeonpunk setting also includes the gritty, cynical tone of Punk/Noir to your standard Heroic Fantasy trappings, but his isn't necessarily true; Post-Punk is a thing, after all.
What really defines this as a setting ideal as opposed to just being a Fantasy Kitchen Sink is that, in addition to the arguable cynical tone, the magitek used is always based on the Industrialized Magic approach; all "technological" devices ultimately owe their power and nature to magic. Be it an aircraft granted levitation & motivation by a bound elemental, a steam engine fueled by super-coal compressed from damned souls or a nuclear reactor powered by crystallized evil, feats we achieve through technology are instead achieved through the meticulous application of magic, which has taken on technological trappings due to being understood so well.
- Eberron, with its entire setting built around magitek of the Industrialized Magic variety, its magical trains/planes/speedboats fueled by bound elementals, and its artificial soldiers, is a iconic example of Dungeonpunk. Hell, it named Dungeonpunk as a thing.
- Planescape actually originated certain elements of dungeonpunk, especially in term of visuals and cynicism.
- Iron Kingdoms, and its predecessors Warmachine and Hordes, is a perfect example of Dungeonpunk with added war themes; the setting revolves around using steam-powered clockwork-based golems under the charge of wizard-artificers to do battle, after all. It has a more optimistic Post-Punk attitude, however, leading to its designers referring to its style as "Full Metal Fantasy".
- Spelljammer is a wacky Space Opera setting on the surface, but it has a Dungeonpunk heart, what with how the setting revolves around enchanted ships crafted to fly between different planets.
- Ravnica, the City-Plane of Magic: The Gathering fits this, being a world-spanning city-complex that relies on magic to make its infrastructure work.
- Shadowrun has traits of this, but is thought of as more of a cyberpunk setting with added magic & fantasy than a fantasy world built up into cyberpunkish magical levels.
- Exalted has some aspects of this.
- The Eldar of Warhammer 40,000 are Dark Fantasy Space Opera Cyberpunk take on this, with hyper-advanced technology that ultimately depends on their race's natural affinity for psionics.
- The Skaven of Warhammer Fantasy have advanced technological gear, including wide-spread electricity, that ultimately stems from their using crystallized chunks of pure madness & corruption as everything from fuel to ammunition to medicine.
- The "superscience" in Deadlands is all powered by Ghost Rock, a greenish-black coal-like substance full of white streaks that screams horrifically when burned. Because it's actually the souls of the damned compressed into a physical material, and when the stuff is burned, the spirits are released back to Hell - quite painfully.