When my office was in the old Chronicle Building on Sprague Avenue, I frequently had passers-by tap on the window -- often school kids lined up and waiting to go on field trips. That hasn't happened since I moved to the fourth floor of the S-R building.
Until today. Maybe the window washer was just being friendly, but I suspect it's SOP to alert office occupants so they won't be startled or do something embarrassing. Either way, it got my attention.
What's getting your attention today?