There is a special ongoing deal now with the NYC Conv & Visitors Bureau offering parking for as little as $3 along with a metro card or something! Tough to beat!

Remember, after so many years as a student, I still just park on the street!

Also see:
http://www.flyertalk.com/forum/Forum94/HTML/000170.html
http://www.flyertalk.com/forum/Forum94/HTML/002161.html