This is more or less the classical dungeon maze of rooms and corridors. A bit chaotic maybe, but it plays quite nicely.
Another example of the "rooms and corridors" dungeon generator.
Semi-natural caves. In this example the density of the rock was chosen a bit low, so wide open halls intersected by round, pillar-like rock structures have been created.
Rooms, a bit similar to the structure of houses or basements.