Just felt a small earthquake. I thought the chair moving was my imagination, then I thought there was a heavy cart rolling through the building, then I thought someone was trying to get into the neighboring office door by banging on it.
But stepping out into the hallway, there was no one there.
I realized the door nearby was rattling on its own accord -- because -- as I held on to the doorjamb and felt the floors and wall sway -- the whole building was shaking.
By then, other people were trickling out in to hallway, asking if they were feeling the shaking as well. A few more moments, and it stopped, and little groups began to form to talk about what happened, and quite a few people were forming groups outside and calling others on cellphones. Despite one person's ideas that something blew up in the basement, it was soon confirmed to be an earthquake.