Grand Central Terminal
The clock atop the information booth has been valued at $10 million to $20 million. The four faces are made entirely of solid precious opal. This 1913 clock is mechanical and still runs on Swiss motors, but is also set constantly with the atomic clock in the naval observatory in Bethesda, Md. So next time you walk through Grand Central, set your watch, the clocks in the terminal are accurate within 1 second every 1.4 million years.