[bzbarsky]

If you include welfare state benefits (which have wage-income-based phaseouts) in income, it's not hard to produce such examples. http://mises.org/daily/3822 has a simple case which has >100% effective marginal rates between about 20k and 50k for a family with one adult and 2 kids.

_That_ is the sort of thing that could go away with a guaranteed basic income. At that point, you'd just have taxes, which do in fact behave as you describe.