Yellowstone Club Ski Resort, Montana

Likely the largest of the few fully private ski resorts, this 15,000 acre private ski club north of Yellowstone Park, has more than 2,200 skiable acres and 15 chairlifts - more than some major commercial resorts - as well as other summertime recreational amenities (like a golf course). The benefits of course include privacy, security, untrammeled trials, and shorter lift lines. In order to be member though, you must own a house there, and the smallest condos start at $4 million. Plus there is a $300,000 joining fee, and annual dues of $36,000. The project went bankrupt in 2008, but since then has sold more than $1billion in real estate.  Tech magnates such as Bill Gates and Eric Schmidt are members, as are celebrities like Justin Timberlake and Ben Affleck. To keep the crowds out is a security system managed by former secret service agents. And membership is capped at 864 households.