And not in a good way...

[rorqual]

So, this unearthly low humming rumble started up outside the trailer, and got louder and louder, until I had to go to the window to see if the world was somehow coming to an end in a weird, unexpected way. And there's a massive backhoe out behind the building, right on the other side of my wall, doing some sort of Work I can't quite identify (but which probably involves digging). The noise is so loud and low that it vibrates my whole office, floor on up. It's distracting me from my very tasty peanut butter and jelly sandwich. It may be slowly shaking the bubbles out of my coke and making it flat...

Oooh, now it's gone.

Eerie.