Friday evening's commute back to my car was almost a disaster.

I was riding my upright bike, and my pannier fell off (again), with the laptop in it. This happened as I was crossing the bridge in heavy traffic.

Luckily the car behind me braked to avoid running over the bag, but he was following pretty close, and the bag was under the front of the car when he stopped. I ran back, grabbed the bag, jumped on the sidewalk to get everything squared away, and waved to the driver.

If I use the pannier on the upright bike again, I'm gonna zip-tie it to the rack.