I had a broken NES, a rotary tool, two small hinges, some glue and Alpha Flight's Sasquatch. What I ended up with was a lunchbox that gets all kinds of funny looks.
This is my first project, and kinda sloppy. I only had about two hours to do the whole thing. I'm sure I'll improve it over time (add a latch and file down the rough edges some more) but for now, it holds my lunch admirably.
Step 1: Remove the guts
Opening the NES case and pulling out it's guts is pretty easy. Take out all the screws you can find and lift the parts out gently one at a time. The wires can be unplugged from the motherboard pretty easily. I had to use pliers to get a decent grip on them though.
Step 2: Remove the wires
Removing the wires from the controller ports is a little more tricky. They will pop out with some effort, but you may just want to clip them off and file the sharper ends down.
Step 3: Power and Reset buttons
Once you unscrew the circuit board that these are attached to, they pop off really easily. Save these so that you can glue them back into place later.
Step 4: The plastic posts
I wasn't ready for all these little plastic posts that are inside the bottom part of the case. I couldn't even fit a bag of chips in there like that.
Step 5: Rotary tool action
The best way I could think to deal with the posts was with gratuitously unsound use of a rotary tool and a a couple of cutting wheels. This was by far the longest part of the process.
Step 6: Better
Once the posts were cut off, I ground the nubs down with the rotary's sanding attachment. Now it's nice and roomy in there. I left the 6 larger posts intact since they were originally intended to hold the case together. I thought they might help to add some stability.