Even if things may not have "taken off" by some measures (and some of the first products truly never got out of the phase with a few pilot customers), I am extremely proud of what we have been able to do with TapBookAuthor.com with no external funding since 2011. All the major publishers in Norway are customers and we also have customers in exotic, and less exotic such as San Francisco and London, places all over the world.
Today I met with an author that was so inspired by our tool that she was shivering from the opportunities it opened (we are working on our business model and technology to help indie and stand-alone publisher-authors, and are running a beta program to learn more). Such experiences makes it easy to find motivation for an extra long night of working (I've had my share of such late working nights, or to paraphrase Joey from good-ol' Friends: Actually, I've had a lot of people's share!).
If you read this and are considering to do the same and start your own company, should you do it? I will not claim it is easy and I am still not quite used to the insecurity of not knowing the economical situation just a few months into the future. That being said, I can honestly say I have never regretted jumping. So I would say jump, get the experience and find out for real if it is your thing. And unlike being pregnant, there is even a way back if it should not work out for you. Good luck!