Doored from the left
On my morning commute last week, I was coming up to a red light. I was passing a long line of cars stopped at a red light during the morning rush when a (shotgun) passenger opened his door in front of me. I hit the door and went down, but my bike and I escaped with just scrapes and bruises.
To their credit, the passenger and driver stuck around, even though other drivers kept honking at them to move. Welcome to Chicago! The passenger was clearly shaken up, to the point of tears. I felt badly for him.
Fortunately, a good friend was riding behind me. He spoke with the driver and passenger and took pictures of their driver's licenses, while I laid on the sidewalk collecting my thoughts. Other nice strangers checked to see if I was okay. Welcome to Chicago! We finished our commute and I patched myself up at work.
Coincidentally, on my commute home the night before, I was trying to estimate how many parked cars I've passed without getting doored. I didn't come up with an answer better than "a bunch." I never thought about getting doored from a car in the driving lane, but I do now. Not in a fearful way; it's just one more thing to notice. Watch out for doors on the left.