Sunday, April 25th, 2010, I picked up several packages of CFL at my local Costco at a great price. In fact the price made it close to impossible to pass up.
$0.99 bought a four pack of 13 Watt CFL (60 Watt replacement) after instant rebate taken at the register.
$1.79 bought a four pack of 23 Watt CFL (100 Watt replacement) after instant rebate taken at the register. 
The package label indicates the 13 Watt last 13 times longer; save $369 per pack of 4.
The package label indicates the 23 Watt last 10 times longer; save $225 per pack of 4.
Nice deal – great way to save on your electric bills.
>>>>> Remember Home Depot collects CFL for safe recycling.
Via: Costcp LINK