This is interesting, especially the copy of the New York Times that was found inside a girder.... nothing special about that, except it is dated 1969 and placed there during construction.
http://www.pbs.org/americarebuilds/artifacts/artifacts_05.html
Among the more surprising finds, this newspaper came from inside a steel girder put there, presumably, by a worker during WTC construction. "Construction guys often create their own time capsules," said Wagner. Other items recovered from girder interiors were old soda and beer cans.
http://www.pbs.org/americarebuilds/artifacts/artifacts_05.html