Less understood facts about Bitcoin. Did you know all of them? What's your own factoids?

Some fun factoids to annoy your new Bitcoin friends with:

1. Bitcoin does not a have "price". It is technically a money. You don't say, "what is the price of Euros"? It's technically a "rate". Andreas explains this in his intro to Bitcoin class. We have just made it a culture to say price, because normies think of it like a stock and we also see it as property and capital, so "price" was easiest way to express the value.
2. There are exactly zero "Bitcoin" in the network. Actually, Bitcoin doesn't even know what a "whole bitcoin" is. It knows sats, and only sats. There almost 21 quadrillion of them. Which brings us to the next one:
3. There are NOT 21M Bitcoin... and there never will be. There is juuuust under that amount in issuance. It's very close to 21M though, so that's what we say to make is easy.
4. You always get "change" back when you send Bitcoin. You only possess "chunks" of Bitcoin, called UTXOs. You actually overshoot the amount of Bitcoin you send, and whatever you had to overshoot it by, you get back as "change", in a sense. A return transaction automagically goes to your wallet with your overage. This is vital for Bitcoin's settlement functionality

What's your fun factoid most newcomers don't know yet?