A mid-sized regional airport, a little bigger than La Guardia, located in Ronkonkoma NY, the center of Long Island. Southwest Airlines is the most busy there, with non-stop flights to Chicago, Las Vegas, Palm Beach, Ft Lauderdale, Orlando, Tampa, Baltimore, and Nashville. American Airlines is the second most busiest, with non-stop flights to Cleveland and Atlanta. Delta has non-stop flights to Cincinatti and Atlanta. Continental flys non-stop to Boston, and US-Air flys non-stop to Philadelphia. Other small airlines come and go. There is also a flight school there, with LOTS AND LOTS of small planes (cessna, piper, beechcraft ect.), which are also rentable.
It cost less to use LI MacArthur rather than JFK or La Guardia.