This is one of the most impressive up-cycling projects I've ever seen. It started out as an aluminum drink can, and turned into a beautiful embossed box. The maker, Atomic Shrimp, started the project with an empty Emerge can, a strong pair of scissors, a cork-backed table mat, a pointed object (like a scriber or even a ballpoint pen), some tape and fine abrasive paper.
First, the can was cut down one side.
Then, after it was trimmed, it was taped onto the cork back of the table mat and sanded with the abrasive to remove the can's paint.
Using a the scriber, the maker marked out a decorative pattern.
After that, the piece was cut to shape with the scissors and then folded into the box shape.
Atomic Shrimp has a thorough pictorial of the process with some added tips if you think you'd like to attempt such a project.