In one project, I worked with an experienced furniture designer called Ken Reinhard. He would sketch up designs (pen & paper) and my job was to solidmodel his creations for fabrication and rendering. This is just one example of many.
3D Printed Parts
Here is the spring mechanism which pulls out a cartridge once it has been duplicated. You can't beat 3D printing when designing mechanisms.
Over the years, I've worked with some great companies where I picked up a lot of electronic packaging experience. The entire systems – boards, chassis, connectors and cabling were all modeled up in Autodesk Inventor. (1000+ components). We even used CFD (Computational Fluid Dynamics) to forecast how well the heat sinks would perform.