Wow, so many to choose from. Plus so many neat posts!
My first night camping in the back country in the Smokies, EVERY sound was a bear coming to eat my head. My son slept like a rock next to me, the joys of being 10 & ignorant. (OMG, that was a long time ago, he's 32 now)
I was last in my group on the AT, had decided to hike further than planned cause it was a good trail, clear night & perfect weather. I hit a large patch of slippery roots on a 90 degree turn, tried to turn, kept going straight, towards a very tall cliff (I'm guessing 200', not straight down, but steep enough that I would have been hurt.)
Thankfully there was a sapling just large enough to keep me from going over, I held on to that tree for dear life. Yea, took a few minutes to slow down my heart & remember to breath again.