A heat sink for an LED downlight utilizes tilted fins forming helical air passages that can enhance thermal performance by 30% over conventional fins. To overcome the thermal challenge of installation within the stagnant hot air of insulated ceiling cans, a heat sink has an integral electrostatic air pump on its exterior, to move hot air downwards and drain the stagnant air from the can by establishing a chimney-like circulation up through the heat sink and back down around the outside of the heat sink. The air mover can be powered by a compact high-voltage, low-current power supply similar to those of neon signs. An embodiment of the heat sink is also revealed that is suitable for cooling an LED replacement for standard screw-in or equivalent light bulbs. This device can perform well in variety of orientations (horizontal, vertical, etc.) and fixtures.