This is a great way to spruce up your dull flash drive and fool your friends into thinking that you re-wired your controller for storage. Note- If you can't stand taking apart a piece of Nintendo history this is not for you.
Step 1: This is what you need
Materials that you need-
1- a NES controller, ( hopefully one that is beyond repair and you were going to throw it away) If not you can usually find some at a Goodwill (which is where I found mine) or a thrift store.
2- a small USB flash drive. It needs to be small and skinny so it will fit inside the controller ( I'm not sure the brand of mine because i found it in the dryer at my apartments ( and it still works after two years!)
3- a USB extension cable. I used a short one but you can use any kind you want as long as the female end when attached to the drive fits inside the space in the controller. Mine came with a SD card reader and I never used the cable with it.
4- a NERF dart (or firm foam) I'll explain why you need this later.
5- a screw driver with a head small enough to fit in the holes in the controller.