Called the office, which of course means I actually called the office's answering service. Of course, they immediately understood that this was an emergency maintenance thing... BECAUSE THEY COULD HEAR THE ALARM THROUGH THE PHONE! So they were helpful and said they'd page emergency maintenance.
So I looked around some more for anything that could be causing it... couldn't see anything. One of the security system in-ceiling sensors was blinking like it was going off, but I couldn't figure out what was doing it. So I opened the vertical blinds on the living room door to the patio, and a few seconds later the damn things shut off.
Then Lis heard a noise in the front hallway, and I heard it to. So I went to investigate it... and there is water dripping from the smoke detector. This is not good. Called the office, er, answering service again and they said they haven't heard back from the emergency maintenance page. I told them what I had discovered, and the service said they'd ask the maintenance guy to call me when they call to answer the page.
Of course... this is really good "emergency maintenance". How long should I give them before I call the answering service and tell them to just not bug me until 8am... *sigh*