Charge pump circuit to multiply the input voltage. Here the circuit has been used to make the output go three times the input voltage. More capacitor stages can be added to get higher voltage. Clock input has been provided by the IC555 which connects and disconnects the pump capacitors to the ground and allow them to charge and then force the charge into the main capacitor respectively.
However, the voltage is not very good for running good amount of loads as the voltage drops significantly when loaded but can be used for something drawing few miliamps but needs higher voltage than your battery.
