What about parts for the Bloodhound SSC land speed record 'car'?
http://www.bloodhoundssc.com/blog/pr...steering-wheel
Above article is mostly about printing the steering wheel but it also mentions them looking to print the air brakes - so subject to a lot more stresses- & I have personally seen a prototype nose cone that is printed from a titanium material.
From what I've heard, the reason 3D printing isn't 'bigger' isn't really about strength but that you still can't just print something & use it (in 'metal' structural items particularly). There are still machining costs on top of outlay for printer & medium etc. So, they are still reserved for designs impossible to produce in another way (in one piece?) & for minimal waste of really expensive material - like titanium.
It's a great technology & just a shame that 'sensationalist' stories about making guns are the main thing the average person has heard about them!