Negative Voltage Generator for Low Voltage ( +1V ) Input
Most analog circuits work better on a bit higher voltage than 1V. If you use a single cell charge pump or inductor step-up to, say, 2.7 or 3.3V then you can use an inverting charge pump to get -2.7 or -3.3V. Of course the current draw will be multiplied by the voltage ratio plus losses. 

Eg. LTC1502-3.3 + LM2776.