There are some incredibly original ideas that people have realized with LEGO building sets. A number of sites like rebrickable.com showcase these creations.
This 3D Doodler was invented by a design student to address the issue of reducing packaging waste and increasing recycling via monomaterials. In some articles, this is misidentified as a 3D Printer, but it is more correctly termed a 3D Doodler since a human is basically drawing in space rather than on a 2D sheet of paper.
Monomaterialism creates products and/or packaging out of one material rather than several (plastic bubbles, foam popcorn, paper and cardboard of different types) thus making things cheaper and most energy efficient to create and recycle – topics related to this years FLL challenge Trash Trek.