We love 3D printing.  It's a big part of one of our most popular courses, and we have half a dozen in our own office that we use to print parts for things like our Laser Tag system.  They can be one of the more frustrating technologies to use, though, and it's important to know the basics like the importance of leveling the bed properly and getting the first layer right.  Doing some simple maintenance on the printers is also important, and something we try to teach the campers.  This video is a great introduction to some of the more important things to keep your printer running smoothly.