Bill Hammack is The Engineer Guy on YouTube, where he explains the complexity behind everyday objects. Hammack is also a professor with a long track record in engineering work. As a communicator, he's able to bring out the wonder of engineering in even the simplest objects—and today's is the disposable diaper.

I'll be clear up front: There's nothing gross depicted in this video. It's classic "Let's pour some blue liquid on here" stuff. Hammack takes apart a typical disposable diaper and explains the complex technology in its various layers. I have never been so absorbed by a six-minute discussion of absorption (and repulsion) tech. Enjoy: