• A Compact Fluorescent Bulb (CF) lasts 10 times longer than an incandescent bulb (750 hrs vs 6,000 - 10,000 hrs) .

• A single Compact Fluorescent Bulb uses 1/4 the energy of an incandescent equivalent and saves $30-50 or more in bulb and electricity costs over its lifetime! **

• Over its lifetime, one single Compact Fluorescent Bulb prevents 600-1,000 pounds * of carbon dioxide from heating the atmosphere. It also prevents the emission of 5-10 pounds of sulfur dioxide, which causes acid rain.

• The same Compact Fluorescent Bulb will also save the time and trouble of buying and installing a dozen ordinary bulbs.

• Old fluorescent tubes gave off an unnatural and unpleasant bluish-green color and the ballasts were magnetic which caused the lights to flicker at 60 Hz (cycles per second). Today's fluorescent tubes and bulbs are vastly improved. State-of-the-art rare earth phosphors show true colors and natural skin tones. And flicker is totally eliminated with new electronic ballasts that operate as high as 20,000 Hz.
• CF bulbs contain about 4 milligrams of mercury sealed in the glass tubing of the bulb (roughly equivalent to the tip of a ball-point pen). Therefore, compact fluorescent (CF) bulbs or fluorescent tubes must NOT be thrown away with your regular garbage. Put them in a plastic bag and take them to Home Depot, IKEA or Hazaderous waste programs in your community.
• Broken Bulb Cleanup: You do not have to have a HazMat team come in to clean up after a broken bulb as one Internet email message claims.
  - You should sweep up (don't vacuum) the pieces and place them in a plastic bag followed by wiping with a damp paper towel which you also put in the bag.
  - If weather permits open windows to ventelate.
  The Maine site below says you should also wear protective clothing.
  See sites below for details:
  Snopes.com
  Mercury Fact Sheet at EnergyStar.gov (pdf) from the U.S. EPA & DOE
  Maine Bureau of Remediation & Waste Management
• Unless specifically noted on the packaging, CF bulbs do not work in any type of fixture that uses a dimmer, either on the wall or as part of the fixture.
  
• It is a common myth to believe that switching on fluorescent bulbs use more power than operating them for short periods of time. The initial start-up, or surge of electricity, is very small and only lasts for a millisecond.
• The light does not travel as far and a CF bulb in an enclosed fixture can cause the ballast to fail prematurely. That's why we don't recommend putting CF bulbs in recessed fixtures. They don't have the "punch" that incandescent sources have.
• After about half of the CF bulb's life, light output can decrease by as much as 25%. But if you buy an Energy Starlabeled CF bulb, it must lose no more than 10% of it's total light output at 40% of it's rated life.
  
• Because fluorescent sources emit light differently than incandescent sources, a CF bulb with the same lumens often seems dimmer than a regular bulb. Light from an incandescent is called a "point source". All the light comes from a single filament resulting in a large glare when you stare at it. But with a CF bulb, the light is distributed evenly from all around the tubes so when it meets your eye, it seems less bright.
• When under a lamp shade, less light travels down to your task; for instance when you are reading or knitting. More lumens go up from the shade. That's why we recommend using a circular CF bulb for use under a lamp shade when you need task lighting.
  

** Costs          75W Incandescent  25W  CF  ***
Bulbs                     $0.80       $5           
Total                     $8          $5      Assuming 10 Incandescent
Electricity  @ $.10/KWH  $60         $20      life of 8,000 hrs
              Total      $68         $25      Savings $43

A Consumer Reports update in May 2008 found that: Feit Ecobulb ESL13T bulbs ($2.25) failed between 3,300 to 3,900 hours of lighting in our tests, which cycle them on and off. The package claimed 8,000 hours average life.
The Feit Ecobulb Plus ESL13T/Eco ($2.66) passed a 5,000-hour preliminary test, and they are being tested further, along with other brands. So far, here are some other good choices: GE 8,000 Hour Long Life 41525, and N:Vision 423-599, (sold at Home Depot) were still on after 7,600 hours. We paid about $2 to $4.50 a bulb.
All of the bulbs we are testing claim to have less than 5 milligrams of mercury. Ecobulb Plus claims less than 2.5 mg.
Although not all CFLs will last their claimed life, our testing has shown that most should last much longer than incandescent bulbs and pay for themselves in energy savings.

Links:
CF Info at Seattle.gov (seattle.gov/light/Conserve/Resident/cv5_lw2.htm)
FAQ's at Kansas City Power & Light (www.kcpl.com/residential/CFLfaqs.html)