For me it is the fact that our blood contains iron. I earlier used to believe the word stood for some ‘organic element’ since I couldn’t accept we had metal flowing through our supposed carbon-based bodies, till I realized that is where the taste and smell of blood comes from.
Also fun, they rely on quantum mechanics.
Individual “bits” on a SD card are electron buckets that are either “full” (they have an electron) or not. 8 bits to a byte ~1 trillion bytes to a terabyte.