What is the scariest thing that has happened to you?

About three years ago I was cycling back to home from my ex-girlfriend. It was already dark and a there was a little bit of rain. First of all I saw something white in the left corner of my eye, but when I looked it was just a white curtain. But I swear it was somebody, have me chills. Then later, outside the village, I saw another cyclists red back light flickering far away and mentioned he stopped. When I looked away and bank, the light was gone. This happened like 3 times on the one-hour trip. Every time, like a minute later I could spot the red light again. But than, I got close to "him". Looked like an old man wearing a head. I went passed him and when I looked back 20 seconds later, he was gone.