Extending Satellites' Lives

At least two companies are developing satellites that can repair and refuel other satellites in orbit.  Such capabilities would be big pluses economically, allowing governments and corporations to save money by extending the useful lives of satellites rather than building and launching new ones.

That would also help alleviate the space debris problem.  Fewer satellites launched should mean fewer derelict satellites in an absolute sense-- and fewer spent rocket stages, etc.  Beyond that, the ability to interact with satellites in orbit opens the possibility of safely de-orbiting them when they are no longer useful.