D.H.
As a Mom of a recently graduated from college son-I can tell you that he loved getting gift cards and cash. He mostly got cash and then we put it all together and made a list of what he needed to set up housekeeping/apt/etc. Then we went and bought just what he needed. It was great.
For his friends we mostly give cash and sometimes for his closest friends we would give a check plus a smaller denomination gift card for itunes, movies or restaurants. One of his friends that just graduated from college is a big fisherman so we gave him a $25 card to Bass Pro and then a check for $50. He seemed to really like it.