or "so *that's* what that key does".
After a 75 minute cardio workout, and a 20 minute walk home, I traditionally want little more than dinner and a shower when I get there, and I want it very badly. Tonight, I get to my front door, and... it's blocked off. Oh bother. That's right, they're resurfacing the hardwood floor in the lobby. Fine. Walk around to the side entrance. Get in the elevator, and...
The fire alarm goes off.
One guess why! Fire detectors *love* lots of little airborne particles. What could possibly go wrong? I considered heading to the bar across the street for food and a drink, but then I remembered: where there are fire alarms, firemen are soon to follow. I was not disappointed. Except when they left. Ahem.
ANYway, since the elevators weren't working, I had to take the stairs (why yes, climbing 5 more flights was *just* what I wanted at that moment, thanks for asking). And that's when I discovered why I had that mysterious other key that I'd never had use for. It opens the stairwell door on my floor. Good to know.