Simply awesome!

Thanks!, JaCoB applet is the best for this purpose for students to try to figure out themselves.

I managed to follow your video to get the same effect setup as in the question.
http://www.phy.ntnu.edu.tw/demolab/CoLoS/JaCob/
I have to make a video about this when time permits. It is super powerful

The embedded applet appears to be of a different character system? i see squares for the english words :)