Last week, I learnt (as I thought) that switching the direction of the air conditioning in my car from "windscreen and footwells" to "footwells only" made it blows cool air straight out of the dashboard vents at me.

Today I learnt that there is actually a fourth icon on the dial, in addition to "windscreen only", "windscreen and footwells" and "footwells only". It is, unsurprisingly enough "blow air straight out of the dashboard vents at me", and is right at the far side, past "footwells only", so when I thought I'd set it to "footwells only" I'd actually set it to blow the air straight at me. Which it then did, unsurprisingly enough.

(I hadn't realised the fourth icon existed because it's on the passenger side and the knob blocks my view of it from the driver's seat. It's not like I've had the car two and a bit years or anything.)