One of the largest leases ever signed to that date was the $115,000,000 lease to build a skyscraper above Grand Central Terminal for was was to become the largest commercial space in the world.  The building was crowned with a large Pan Am Sign; the visual impact caused the New York City Zoning Law to be changed to keep permanent signs off of buildings.  On top of the building was a heliport which whisked first class passengers off of the roof to Idlewild (now JFK) which was about 10 minutes away.