The digital revolution has fundamentally changed our lives. Multimedia content-creation tools allow us to instantiate and share ideas easily, but most outcomes only exist on-screen and online--the physical world and everyday objects are largely excluded from a parallel explosion of mechatronic object creation. Services like Ponoko and Shapeways allow professionals and non-professionals to access computer-aided manufacturing (CAM) tools like 3D-printing and laser-cutting, but there are few (if any) design tools for creating complex mechanical assemblies that take full advantage of CAM systems. Creating unique mechatronic artifacts�Original Machines�thus requires more specific and sophisticated design tools than exist today. Object-oriented mechatronics is a parametric design approach that connects knowledge about mechanical assemblies and electronics with the requirements of digital manufacturing processes. The approach addresses the missing link between accessible rapid-manufacturing services and currently available design tools, creating new opportunities for self-expression through mechatronic objects and machines.