I was second in line at a red light in the left turn only lane. I watched the small car in front of me start inching forward slowly, brake lights still on. They continued across the stop line, and into the intersection right in front of a full size dump truck doing 50 mph who was forced to slam on the brakes and come to a complete stop!
I have no idea why the driver did this, (although fiddling with their cell phone comes to mind) and thought for sure there would be a nasty collision. I was never in any danger, but later kicked myself for not being quick enough to think of hollering out to the driver.