I find it interesting how, when I (e.g.) yawn while listening to music, I get a kind of pitch-bend effect. Reminds me how ears and nervous systems and things work, and that they really don't present reality to your consciousness the way you might expect if you're used to computers and other human-designed technology, but do a lot of preprocessing and, well, Weird Stuff™ to give your brain something that natural selection thinks will be the best interpretation of reality to keep you alive and reproducing.

Having grown up with tape as the main method of audio storage and reproduction it feels weird to have the pitch change without the speed changing too, but it reminds me that it's actually all about the little hairs inside the cochlear, and how vibrations propagate through the fluid and which hairs each incoming sound frequency ends up stimulating. Squish things around by yawning and the link between specific frequencies and specific hairs changes.

It reminds me of other things that show just how weird bodies and minds are, such as the stopped clock illusion. Your brain literally makes up stuff to keep you from realising how bad your senses are at their job. It's all so astonishingly messed up.