I grew up on the east coast of the United States. There were plenty of woods around around our neighborhood. One night, I was in about 4th grade, I slept over at my friend's who lived next door. My parents wouldn't let me sleep over at friends houses very often, I don't know why, so when I did, it was a treat. The night was fun as I recall it, his whole family were big sci-fi nerds like me, and they had all the coolest toys. We go to bed, my friend has bunk beds and he sleeps on the bottom bunk, so I take my spot in the top bunk and fall asleep.
At some point in the middle of the night I wake up to something tickling my chest. House is silent, everyone's asleep. I reach my arm up to stretch, as I groggily look down to see the biggest, fattest wolf spider I've ever seen. I would hazard a guess that it was the size of my grown man palm or bigger.
I never did like spiders, but at that point I was in sheer terror. I think I tried to scream for help, but I didn't want to move, and I think it just came out like whispered "he-he-heeh...". I closed my eyes and sat there motionless hoping it would eventually move off of me. I have no idea how long I was there like that for, maybe a few minutes maybe an hour. I couldn't bring my self to open my eyes to look because it was taking my entire wherewithal to not piss the bed. As I laid there, I couldn't tell if what I was feeling was the spider slowing moving off of me or phantom sensations.
Eventually I composed myself enough to open my eyes, I couldn't see the spider anywhere, but I wasn't gonna stick around to find out if he was in the sheets or something. I snuck out of bed, out of the house and back into my house & room. I totally abandoned my friend, in his room with satan walking around. And his parents, who thought I would be joining them for breakfast the next morning.
One of the other scariest things I've woken up to was my Mom busting open my door, sighing into the phone "yeah he's here, thanks...", then slapping me in the head and yelling at me, what was I thinking, this is why we don't let you sleep over and so on and so on. But that one was absolutely worth it.