A new study by the EPA (pdf) shows that, if you consider the whole life-cycle, a huge chunk of greenhouse gas emissions (42%) are caused by the way people in the US "procure, produce, deliver and dispose of goods and services".
It concludes that waste reduction and recycling are very powerful tools to reduce CO2 emissions: According to the report's projections, if we were to reduce packaging in general by 50%, reduce non-packaging paper products by 50%, extend the life of computers by 25%, increase recycling of construction and demolition debris to 50%, and increase solid municipal waste composting and recycling to 50%, we could cut US CO2 emissions by about 354 million metric tons of carbon dioxide equivalent (MMTCO2E). Each year.
Read the full story from a Hugger