Oooo, let’s see...
I once memorised pi, and stopped explicitly at 404 places for the reference to a page not found error. I earned a free college class for this, but then dropped out and moved to a new country.
I once wrote an othello clone in assembly; though, admittedly, the AI was rather predictable.
I’ve tried to write code that can inspect, modify, and improve it's own code (AI).
I used graphviz to map out college class interdependencies, international routing paths, and my family tree.
Recursion excites me.
I've sung the Tetris song while trying creative ways to fit groceries into the refrigerator and while cars were stacking up behind toll gates.
After several pints of Guinness, I once laid down a compelling argument in favour of spirituality, using relativity and quantum mechanics as a supporting base.
I sometimes convert people’s license plate numbers to binary or practice saying them in foreign languages to pass time while driving.
Sometimes I try to play chess in my head, or practice piano on the side of a table.
Oh, and maybe the geekiest (or most competitive) of all, I came out of hiding just to “win” this thread.
I'm not crazy. My reality is just different from yours.