The Saturday/Sunday Wall Street Journal for October 6-7 has a special 11 page advertising section for collecting and investing in luxury watches. According to
Frank, Robert. 2007. Richistan: A Journey Through the American Wealth Boom and the Lives of the New Rich (New York: Crown): p. 143: A top of the line Franck Muller watch costs $736,000.
It must be very difficult for somebody earning tens of millions of dollars to figure out what to do with it.