Voxel8’s 3D printer is a game changer. The dual-head machine outputs plastic in standard FDM style, but also has a conductive paste extruder to allow you to create built-in electronic circuitry into your design. That’s right — 3D printable electronics.
Working with Autodesk, they’ve created software that allows you to specify your desired circuit pathways, as well as the location of the electronic components needed for it. Then it does something really slick: It automatically prints the appropriately sized cavity for the components (along with conductive traces), pauses to allow you to place the components into the spaces, and then continues printing, encapsulating them into the design.