A few months I had a chance to listen to a keynote speech by Jeff "Skunk" Baxter at a company event. You may recognize his name as guitarist from the Doobie Brothers and Steely Dan. You may also be really confused as to why this guy was speaking at a conference that I would be at. You see, halfway through his career, Jeff took a passing interesting into ballistic missile defense and began a course of self study. His non-establishment thinking allowed him to make some connections that others had not seen, which culminated in several white papers and a consulting gig with the US Department of Defense.
(Photo: Public Domain: Missile Launch by USN, 2007 - DoD 070622-N-XXXXX-004)
While we could have a long discussion about "thinking outside the box" and the equivalent of scientific "outsider art", I'm going to go in a different direction with this post. I think what Jeff shows is that with enough willpower and enthusiasm you can completely change your career. Given that he most likely enjoyed being a rock star and fostered his enthusiasm in missile technology, other people despise their jobs, but are stuck to them because they cannot afford to pay the rent while not working.
Within the last ten years the advent of online learning has gone from a novelty to a fully accepted reality. It is possible to receive the education and training required to completely change your career, all while working at the job you can't stand. What is required here is setting your priorities and your goals. It can be so easy to become mired in a mindset in which you feel that you have been doing the same job for so long that you can't do anything else. Once you are over that hurdle, you'll find that the things that are required (i.e. Money, time, family support, etc.) will come much easier when you have chosen your path.
On a side note: For those who scoff at an outsider's ideas, take a look at the logical progression of Skunk's white paper on using the Aegis battle command system as the core of a missile defense system, to the scenario that was used in Feb 2008 to take down a dangerous malfunctioning satellite.