This week, Home Depot is expanding their Eco Options program, which will label eco-friendly and sustainable 2,500 products, such as organic plant food and programmable thermostats.

As part of the program and in honor of Earth Day, on Sunday April 22nd, they're giving away one million Compact Floursecent Light bulbs to customers who visit any Home Depot store in the U.S. (If you read the fine print, they really mean the lower 48. Sorry Alaska and Hawaii.)

The Eco Options program offers lots of information and little web-apps, such as one which will calculate energy and cost savings you will gain by switching to CFLs.