I don't think being thin was a goal. It becomes a nice consistent block shape when closed, like a bento box. It reminds me of an old ThinkPad. There are also similarities to the author's previous Cube PC project in its design style.
The hand-wired ortholinear keyboard and small secondary screen are also of note. A laptop with an ortho keyboard is not very common (sadly).
It's not even a good case, there's tons of wasted space, it's bulky, etc.