I know several people who have or will be quitting their day job to become a full time publisher. They make their money from advertisers and AdSense. There are new discussions taking place at WebmasterWorld where people are discussing the pros and cons of moving outside of the United States to find a lower cost of living. This way they can use their Adsense income and live modestly in a place like India or other places that cost less. Maybe even tax free, like the Bahamas.