Dabu!
I spend too much time playing games.
I'm sitting in the living room working today, because it's a really pleasant day, and Bonnie and the kids are out, so I have the house to myself. It's a chance to open the windows and get some fresh air before I have to return to my basement lair.
So I'm enjoying the breeze and the birdsong and the sounds of spring outside, when I hear the distant percussion of hammers striking wood. Someone in the neighborhood -- a fair distance away from the sound of it -- is adding on to their house.
I close my eyes for a moment, because the sound is triggering a sense-memory that hasn't fully formed, but it's just on the tip of my brain ...
.. and there it is. It's the exact same sound that Peasant units in Warcraft III make when they're building structures. The arrhythmic staccato of multiple Peasants collaborating on a building.