Infiniminer is the main inspiration for the blocky design and the terrain deforming. Dwarf Fortress is the main inspiration for the survival game mode, and this is where I want to take the majority of the gameplay.
These are both awesomely entertaining games that you have to play.
And, obviously, I’m influenced by my own work on Wurm Online. This mostly shows up in the terrain generation code and the resource management that will show up later on, even if minecraft is very much a different game.