Milton Friedman FTW!
Yes, I love the idea of a negative income tax compared to our current systems like Welfare, Medicare, Medicaid, HUD housing, food stamps, etc.
It would allow all of the above mentioned programs to be condensed into one program. This would lessen bureaucracy, reduce costs, stop people from being trapped in dependency, and not discourage productivity.
I don't see why it isn't more popular, because it appeals to liberals that like safety nets and libertarians who like the minimum amount of government as possible to manage things.