The other day, Flavia had a provocative post about remembering and forgetting names, and one of her commenters noted that while we tie ourselves into knots about remembering the names of our 40-200 students every semester, many of our students do not remember our names, and they have far fewer names to remember.
This got me to thinking about how I remember many of my students names (I am smug that way) and moreover that I remember virtually all of my professors' names almost 15 years later. And then I thought, "I hope some of my students remember my name in 15 years." And then I thought that just maybe some of my professors, especially the ones with whom I'd have no other contact, in different disciplines and such, might like to know that I know their names still, and more than just remember their names, I remember their impact on me as a thinker and almost inevitably, as a teacher.
Anyway, I decided to look a few up and email them, to tell them thank you, belatedly, for being great teachers. I've gotten one response thus far, from a now-tenured professor who was at the time an ABD adjunct. But I don't really require responses. Mostly I just want to remind myself and them that good teaching does make a difference, even if I am my only evidence.
Anyway, I think that you should do this, too. Figure out which professors would never in a million years expect to hear from you, but who shaped your thinking and teaching in unacknowledged ways. And then acknowledge it. Their email addresses are likely easy to find if they're still teaching, and I can't imagine that the blast from the past would be unwelcome.