While this is fun if you like writing, it's not really a reliable or efficient source of income. It takes me about 6 to 10 months to write a tech book in my sp

While this is fun if you like writing, it's not really a reliable or efficient source of income. It takes me about 6 to 10 months to write a tech book in my spare time, and unless one hits the popularity jackpot at some point, I don't think they will pay off financially. (But published books do make a very nice line on a CV)