Here’s a unique job we did recently for our good customer Irwin Motors. They wanted to have cubes with a marketing message on each face, and be able to stack them up four high.
We printed on coroplast, which is essentially plastic cardboard, often called corrugated plastic. The printed sheets were bent using a heater we built that softens a narrow straight line in a plastic so that it can be cleanly bent.
In order to stack the printed coroplast cubes, we gave them pegs of 1/8″ wood dowel that fit snugly into the flutes. That held each piece in place and keeps things from coming tumbling down if someone bumps into it.