The plastic bag.

Great article from Salon about the ubiquitous plastic bag.

"...The most ubiquitous consumer item on Earth, the lowly plastic bag is an environmental scourge like none other, sapping the life out of our oceans and thwarting our attempts to recycle it."
LINK to article- read it, it's very good, and goes into the paper/plastic thing with all the info you need to smackdown the next fool who claims that plastic bags ger recycled, or claims that they're less damaging than paper bags. Annoyingly, article also mentions those damn "I am not a plastic bag" bags. People got trampled trying to buy those damn things. Dead, for trying to be trendy. Yeah. Argh.