150 Nassau

History: American Tract Society building, built in 1898. Was the tallest building in the world for nine years until the Woolworth Building trumped it in 1905.
Status: Landmark building.
Conversion: Converted in 2001 to luxury residential condos by architects Carl Fisher and Shamir Shah.
Details: 125 units, 23 stories, gym, garage, doorman, concierge.
Price: averages $1,000 per square foot
Availability: limited