What is the most complicated thing you have ever made on a 3-D printer?

Question: What is the most complicated thing you have ever made on a 3-D printer?
- Keywords:
  3d printer,
  equipment,
  object
Asked by 13crooksgeorge to Iain on 17 Mar 2014.
- Iain Moal answered on 17 Mar 2014:
  
  I have never made anything on a 3D printer. If I win, then it will be my first time using one.

Question: What is the most complicated thing you have ever made on a 3-D printer?