In the midst of a family emergency (my grandfather just died) I found myself spending several days on the floor of my uncle's study. I took a look at the toys I'd brought with me from home: a Cypress PSOC, and little LCD screen with an SD card reader, one of those 3D plastic extruder pens with filament and a box of Arduino parts that included a mini analog joystick.
I thought to myself, I'll make a little handheld NES with these parts! It turned out the LCD was bad, but I had great fun making a plastic case with only a filament extruder pen. I found the process fascinating.
I started by making the top. I spent lots of time getting the curved surface of the top right. After that, I (temporarily) glued the LCD, PSOC board and joystick to the top, after which I wrapped the edges in blue masking tape. I drew a ring around the top's edge (onto the blue tape) with my extruder pen. This became the mating edge of the bottom side of the case. Next I started making the bottom ribs. To do this, I used the extruder pen to basically drape molten strings of plastic across the electronics, which I molded by hand as they cooled (the pictures I've attached don't have the little PSOC controller board stick in it; it went under the tall, narrow ribs at the top. I took it out after forming those first few ribs to avoid damaging it).
Anyway, I've attached some pictures I took along the way. Forgive the terrible photography. I was surprised at how well it turned out; normally I just use the extruder pen for sculptures (for this sort of prototyping work I have a 3D printer at home). I'm a bit bummed my little LCD screen is bad, but I have more back home so I'll just have to wait until I get back.