Yale Facebook is a searchable directory of almost all Yale students. Yale students can request not to be included, and as a result, a small number are not in it. Information includes name, hometown, birthdate, residential college and suite number. Pictures cannot be changed throughout your 4 years at Yale, so prefrosh, choose your photos wisely. Used extensively during Freshman Screw. https://students.yale.edu/facebook
Search for any member of the Yale community's (students, faculty, administrators) names, colleges, email addresses: http://directory.yale.edu/phonebook/index.htm
See also YaleMobile for iPods / iPhones.