Compiz effects was truly the killer feature for Linux for 12 year old me :)
14 year-old me set up Linux Mint with this LSD Conky display for my grandmother. I said something like "Well technically it's LSD but it looks cool so don't worry about it".
in hindsight, I do regret not yet being able to supply my <3 grandma with a small dose, might have condoled her senseless fury (dementia rage or so).. RIP