If your professional job is at a non-profit, can you look into changing your job to a for-profit that you can still live with the values? Sometimes I find we avoid the obvious solution which is to get a higher-paying job in our industry. If you're an accountant, for example, look around and see where people with your skill set and experience are earning the most - then go there. If you're at the point of learning new skills which can be turned to generating income, perhaps consider simply upgrading skills in your main career - likely you are already good at it and know the return on investment, e.g. additional education, different employer, different market, etc. I personally find this a lot easier than forcing myself to sell Avon or something (no offense to those who do and enjoy it - I just don't have a salesperson in me).
I'm also nervous about monetizing my hobbies and interests - I've already turned most of the things I enjoy and am good at into my career, the result of which is enjoying those things much less now. The last thing I want to do is to take what remains and turn it into work too.
I think this is Mustachian too - if you read MMM's 'history of the stash', he leapfrogged around for higher and higher salaries every year, which facilitated his rapidly increasing savings rate.
