It's a dirty subject, but someone has to talk toilets and it might as well be me.

As an interior design consultant, I've shopped dozens of low water use models for bathroom remodels in the past. But the truly evergreen bath goes one further with a composting toilet (also known as dry, biological, or waterless toilets). Sure, some of them look as appealing as a bad motor home or an above ground hot tub, but more stylish choices are coming to the market for those of you committed to self-contained systems.

Take the Envirolet: the Chevrolet, as it were, of compost toilets. The toilets use little or no water, chemicals or septic tanks. They cost a bundle - from $1700 to $4,000 - but at least it's not money down the drain (sorry).

These systems are best suited for remote sites or light use, and maintenance requires diligent attention. Unlike a septic system, the toilet relies on conditions where bacteria break down waste (as with a yard waste compost system). The end product, called humus (please don't confuse with the dip), should be disposed of by a licensed septage hauler. In some areas, regulations permit the disposal of humus to be tilled into the ground in gardens growing non-edible plants.

Image: Envirolet