Your home’s graywater (from showers, sinks and clothes washers in some areas) can be recycled to be used in toilets and to feed your landscaping and gardens, as does this Tiburon Bay house built by McDonald Construction & Development in California. These systems may seem straightforward, but they can be complicated and can cost tens of thousands of dollars. Also check with you local building codes to see what you can and cannot do. A good primer is at Greywater.com. Blackwater (water from toilets and often kitchen sinks and dishwashers) recycling is also used in some uber-green homes. Graywater and blackwater recycling systems are best suited to new constructions.