It is a good idea to wear goggles while doing this, as drill bits and flashing can fly.
Avoid using normal glue or superglue, this can leave stains on your work area and might mess up the components. Use a glue made to glue plastics together.
Lay the pen drive on your work surface, and measure its dimensions. Drill a hole of the dimensions of the pen drive into a slab of plastic. Cut out any excess plastic, leaving a border around the hole. Place the pen drive in the hole and use some glue to lock it in place, if necessary.
Put the pen drive in a 3D case Add a tag or a hole to it to use it as a keychain. Add some papier mache, or glitter.
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