Visual

• McCollough effect
  • Tom Scott Video
  • http://www.scholarpedia.org/article/McCollough_effect
  • The "lasts for 3 months" claim is dubious, the article it comes from is entirely pay walled
  • It does have longer lasting effects than most other illusions

Audio

• Binural beats
  • Has spiritual stuff going on
  • Requires stereo
  • Idk if there's anything actually interesting about it