It reminded me of a certain notebook and pen (an expensive set) where each page of the notebook had a unique background pattern and the pen would record the lectures as you wrote.
Later you could put the pen down on a word in your notes and start listening to the lecture just as you were writing those notes.
Or at least as of 2010 when I put it in an Amazon.com wishlist (and #%&^%& but Amazon's search function sucks, "pen" didn't find the "smartpen" by which it's named).
This is indeed the unit a fellow student used. He dealt with ADHD, anxiety, and many other things in conjunction with medication side effects. For him, this was an invaluable study tool.
Later you could put the pen down on a word in your notes and start listening to the lecture just as you were writing those notes.
Can't remember the name though.