What's the small thing you see daily that nobody else seems to notice?

I carried mail for thirty-one years and after a while you start clocking the little constants — the dog at 311 who waits by the fence at the same hour, the way Mrs. Ochoa's porch light flickers one second before she opens the door. Now that I'm retired I still notice them, just nobody to share them with. Curious what everyone else's version of that is.