That moment when you turn your head and you see something blinking in the corner of your eye but when you move to it, it's gone. Then you turn your head again in that particular angle where you see the blinking thing again and you wonder if the universe is sending you secret morse code.

Then you realize it's just your curtain moving in the wind, blocking and revealing a sun ray that is reflected by your monitor stand.

It could still be morse code though.