My laptop lid looks trapezoidal this morning. The top is clearly narrower than the bottom. This is because I am very astigmatic and not wearing my glasses. I can actually read well enough to (barely) make out the small print on the screen, but here's this gross geometric distortion that's a strong persistent visual illusion. It's weird.
The first time I noticed it I didn't realize what was going on. I had to get out a ruler to convince myself that the thing wasn't just styled funny. Apple product, after all. Then I realized, and laughed a bit.
Soon I will put on my glasses and it will go away. (B)