I have chosen to build a can model of a café racer motorcycle, using strictly can part built from aluminum cans and adhesive. Similar to the above photo the model should resemble an actual bike. This is the hardest material I have ever worked with, the aluminum is so thin it dents/ warps quite easily and adheres on contact with the adhesive making every move count. I was inspired by an old Coke biplane I saw at the hobby shop when I was a kid, always wondered how / if I could make one.
Image source: http://www.mig-welding.co.uk/forum/threads/tin-can-models-not-really-welding.34743/