Believe It Or Not, These Aren't Actually Design Flaws

Blue Bristles on Toothbrushes

Blue bristles on toothbrushes aren't just for the aesthetic. The blue dye actually wears off on the bristles when it's time for you to get a new toothbrush. Since nobody really knows when the right time to change the brush is, it tells you itself!

The More You Know

The word "kimono" means "a thing to wear."
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Your brain is sometimes more active when you're asleep than when you're awake.
Bloodhounds are great marathoners.

Post originally appeared on Upbeat News.