It's actually a pretty good game for engineers. Also, it rewards you for having basic knowledge of digital design. Here's a hidden door I made using pistons which were just added to the game.

http://www.youtube.com/watch?v=z98iFceC0zY

Also there's an editor called mcedit that you can extend with python. For example I wrote a little script to trace caves and fill them with dirt.

I couldn't give the game a stronger recommendation.