I have never seen an actual accident take place before, let alone the cliche "she could stop traffic." But both happened at the same time:
We were driving down the road in rush hour at 15 mph.
Up ahead were two teenage girls, probably 14 or 15 years old with swim suit tops on. One of the girl's tops was totally see through in the sunlight. My first instinct was literally: "oh, crap, she is going to cause an accident," so I was being extra cautious about the cars around me.
Sure enough, I see the guy's head in the car in front of us staring at the girls rather than the cars ahead of him and BOOM, he rear-ended the car in front of him HARD since he was too busy being a perv staring at 14yo boobies. I saw it coming so I was already nearly stopped when it happened.
Thank goodness that while a breastman myself, I put the importance of driving ahead of staring at underage boobies.
My wife missed the whole thing and when I told her what happened, she thought I was making it all up. (She usually notices this stuff and points it out to me!)