After playing this for what feels like an hour (and what may have actually been an hour) I'm suddenly noticing square edges a lot more in my surroundings.
holy crap! I just played for two hours ( got to 2048 ) and when i was done everything (win7) looked very square, kind of small and ... old-fashioned? holy crap. It got back to normal after about five minutes or so...
I had that too! Switching back to my IDE I was surprised at how "boxy" my code suddenly looked. It's a really weird psychological phenomenon. I wish I knew why it was happening.