I just remembered something incredibly specific, and thought it was worth writing down. When I was a kid, maybe 5 years old, I recall waking up too early—likely when the sun was just about to rise (5 am?)—and being rather surprised by the visual appearance of my riding fire engine toy. I wish I could find a real picture of the thing, but I don't have it handy at the moment, and the internet isn't turning up the exact toy.
Regardless, the fire engine would've been mostly primary colors: red, yellow, and blue. The early morning light in the dark room shifted the way my eyes (and brain) perceived the colors in a way that I'm not sure I could ever experience again. Because I believe it was the first time I consciously recognized that the colors of my toy (and the world) could change. It seemed unreal, almost shocking—so much that I remember waking my tired brother to show him.
I can almost visualize it now, but I have a biased brain that knows that lighting changes colors. The image above is my best guess. At the time, I was surprised to see what was normally yellow become something closer to white. Also, that the blue seemed brighter than usual, and the red... very very dark. All my stuffed animals looked different too. I'm probably not exaggerating it enough to match the impact of my experience.
Whenever I woke up too early like this, I would bolt up excited to see all the weird colors. Over time, the effect wore off. I'm guessing my brain (as all of our brains do) has caught on to the fact and understands that the color RED changes in different colors of light—that I can still see RED as RED no matter what light I'm in, for the most part.
Odd post, but I'm wondering if anyone else has a memory like this. Color continues to be very important to me, so it's funny that the memory has stayed with me.