Ouch.
I've managed to miss a few critters along the highway from Montreal to Detroit (401). My biggest scare was inanimate: one of the big blue blankets used to protect furniture when moving!
It was night (11 pm), and I was in the middle of nowhere half-freezing & half drowsy. Out of nowhere (it was very humid and slightly foggy, 150-yard visibility, no moon), a 10 foot tall & wide [big] solid-looking phantom came racing straight towards me at around 75MPH. I managed to avoid it, but it was definitely less than a foot from my throttle as I passed.
Two minutes later, I passed the culprit: a flat-bed trailer being hauled by a big-rig. The bed was empty, but there was a stack of those blankets stashed behind the cab, and they were working their way loose from the single tie-down holding them in place. There are no words for the kind of anger I felt at that moment!
That was the closest I've come to having a high speed bladder evacuation.
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Then again, I'm happy to still be kicking around.
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I spent the next hour of the ride thinking about exactly what would have happened had I hit the center of that blanket. It doesn't lead to great thoughts... On the plus side, I'd have had padding.
Francis