Grey Water?

So what exactly is grey water?

"Greywater is wastewater generated from domestic activities such as laundry, dishwashing, and bathing, which can be recycled on-site for uses such as landscape irrigation and constructed wetlands. Greywater differs from water from the toilets which is designated sewage or blackwater to indicate it contains human waste.
Greywater composes 50–80% of residential wastewater generated from all of the house's sanitation equipment (except toilets)."Wikipedia.org

Links
http://www.greywater.com/
http://en.wikipedia.org/wiki/Greywater 
http://www.oasisdesign.net/greywater/
Video
http://www.youtube.com/watch?v=EBWqUfO-aL0&feature=related

Mike