Einstein famously couldn't find a teaching position after graduation, spent 2 years unemployed, then worked as a patent clerk in a patent office. According to wikipedia: "Much of his work at the patent office related to questions about transmission of electric signals and electrical-mechanical synchronization of time, two technical problems that show up conspicuously in the thought experiments that eventually led Einstein to his radical conclusions about the nature of light and the fundamental connection between space and time."

So there's two lessons here, I think: 1. People outside academia can still make important contributions, and 2. spending a lot of time thinking about other people's proposals, separating the good from the bad, and inspire a new, fruitful way of looking at things, or at least overcoming standard mental traps.