So the first thing to understand about this clever gimmick from the German Dream Team of Tony Lackner and Harold Voit is that it is nothing to do with the Brainwave Deck, which is what I first thought when I read the name. It is just referring to the idea as a “Brainwave”! The pen (which works fine as a real pen) is uniquely gimmicked by Tony (or Toni as he is referred to in the instructions) and in many ways reminds me of the wonderful slate put out by Maverick Magic about 10 or 15 years ago called Slate of Mind. In essence it provides you space for a huge hidden crib sheet so you can use this for custom book tests or pretty much anything that requires a lot of memory work – without the memory work! It comes with a couple of ideas but I’m sure you will come up with more. Great idea, all self-contained with nothing added or taken away!