RFID (Radio Frequency Identification) is already alive and well in libraries, but using it to track humans is a relatively new issue. Here is a story about a school that implemented, then withdrew, a student tracking program based on RFID name tags: http://www.eschoolnews.com/news/showStoryts.cfm?ArticleID=5520 . Weak prediction here, but in the future we as user educators will probably keep attendance based on nametags and a reader over the computer lab door instead of relying on sign-in sheets.