What are some fun/quirky things to improve the reading experience?

I was a bit surprised at how many people have liked the floating ghost (now hamburger) that follows the mouse cursor around or the theme chooser. What are some other things that would be cool to add [with the option for a user to easily disable]?

I always wanted to add some ambient sounds to the site? Like whale sounds, coffee shop sounds, etc.

Any others that you all can think of? Terrible ideas are also welcome :stuck_out_tongue: