Recently my daughter wanted a holder for her kayak paddle to keep it from rolling around the top. It's nice to have if you're fishing or want to take your hands off of the paddle to take a picture .
She happens to be a mechanical engineering student, so naturally she was going to make something.
Nope. Not her, not now. They have access to 3D printers at school. 3D printing, if you're not familiar is the process that's very similar to regular ink printing on paper. Instead of ink the machine drops a plastic resin that solidifies into hard plastic. Instead of one pass over a sheet of paper, the 3D printer can make multiple passes to build up the piece into the final design.
She designed a snap-on piece that swivels to accommodate the angle of the paddle no matter where it's placed on the cockpit of the boat. It's two pieces but made in one printing. Nice. Certainly better than a beer can.