Books. All of my recommenders received a book that I thought they would enjoy.
One of the advanatages to actually getting to know your professors is it makes buying thank-you gifts much easier.
Here are the novels I selected, in case any of you are looking for ideas:
-Blood Meridian, by Cormac McCarthy
-You Must Remember This, by Joyce Carol Oates
-Perfume, by Partrick Suskind
All highly recommended...
Oh, and Anna Ivey's a walking cliché.