Actually, some of those drawings were
for a real game project according to this thread
, a gamemaker game that Kenneth Fejer (a guy's name) was apparently working on and probably discontinued. So it wasn't all just to strut his portfolio, but actually for a purpose at one point. I'm guessing most of those materials that don't use copyrighted material are also from other game project he has worked on.
But I totally agree that his artwork is awesome and inspiring. Apparently he's worked on a quite a few awesome projects
, including Contra 4 for the DS.
I'll revisit this later with other good mockups and screens. I sort of wrote this in a hurry, just figured I should correct a few things.