Compact fluorescent light bulbs (CFL for short) now come in a variety of shapes and sizes for virtually all applications. The standard, inexpensive CFL can be purchased for about $3 each. CFL’s last up to 10,000 hours (12-15 times longer than regular incandescent bulbs), so you don’t have to change them as often as the old bulbs. Download a calculator to help estimate savings: http://www.earthinstitute.ca/binaryoak/0effytubes.xls