About a year ago, I saw one of the weirdest reactions that I've ever seen. It was called the Belousov-Zhabotinsky reaction and it's one of the few good examples of an oscillating chemical reaction. I decided to try and do it myself, and this video summarizes the process that I used.
*At the 5min mark, I say 1.5g phenanthroline monohydrate, but 5g is written. It is indeed 1.5g though.