To cut costs and do their small part for the planet, some families are moving into "passive houses," which use roughly one-fifth the energy of a regular home and slash heating costs by as much as 90 percent. 

Passive homes are virtually airtight, extraordinarily well-insulated buildings that...

At $100 million, the country’s number one and record-breaking luxury real estate property was purchased by Russian investor and billionaire Yuri Milner.  The French chateau-style 25,000 square-foot, 11 acre mansion is located in Silicon Valley, showcasing panoramic views of the San Francisco...