Quadropus Rampage is a mix of roguelike and hack-and-slash systems with some deep customization options, upgrade paths, random loot and good replay value that ultimately is held down by some unwieldy controls and a few spots of confusion here and there.
Dungeons of Dredmor is a roguelike with a good sense of humor and tons of customization options to give you incentives to try again over and over. While I feel the items are overwhelming and the maps are too full with stuff, I think it's one of the best dungeon crawlers I've played.