Made in Space created the 3D printer installed on the International Space Station that works in a microgravity environment. NASA has decided to open the design process for some parts for the Station to the public. For example, people are encouraged to submit designs for a handrail clamp to hold various objects (https://grabcad.com/challenges/nasa-handrail-clamp-assembly-challenge). This competition (which ends in February) has cash awards, but I think no award could be greater than having something you designed installed on the ISS!
Check it out!