For instance, this evening I was riding due west as the sun was setting. I slowed down a bit and occasionally held my hand up to block the sun. I was on a feeder road that runs parallel to the interstate; I like to take the byways if I'm not in a hurry. There was no traffic coming against me. The sun rose and fell above the trees as the road dipped and inclined.
Suddenly, the sun hit at such an angle that I couldn't see a damn thing. It was like riding into a lens flare. I slowed a bit more and then suddenly saw that the road came to an end. Just ran out. I braked as forcefully as I could without skidding and came to a stop with my front tire at the very end of the pavement. Another couple of feet and I'd have tumbled into a grassy ditch.
The hills in the road, the position of the sun, the tree line... they had all conspired like a ballet company to create the perfect conditions at just the right moment to dump me into a creek. I laughed like a maniac, swore liberally, and tip-toed my bike backwards far enough to turn around. I found another route to the coffee shop, one with better visibility.
I learned a lesson about taking sunset seriously, so it probably won't happen again. Next time it'll be something different.
Ride safe, everybody!