As usual, our electricity has been flickering on and off for no good reason.(MetEd, I love you!) Yet even when our lights die and our digital appliances reawaken flashing an urgent green '12:00', my eMac stays running and fully functional. The outages only last for about 10 seconds, but our other computers, including an iMac G5, are shut off by the power loss. Why does the eMac stay on? Does it have an emergency battery or something?