If you live in Japan and are looking to lower your household electricity bill, you might have to empty your bank account first. Sharp recently introduced its new line of ELM-branded LED ceiling lights and the highly energy-efficient, square-shaped bulbs won't come cheap -- retailing between 35,000 yen (about $456) and 55,000 yen (about $717). Pulling inspiration from the LEDs used in LCD televisions, the company was able to achieve an industry-leading 81.3 lumens per watt for the smallest of its three designs, and an average life of 40,000 hou