I just stumbled on two excellent videos. The first one is about the Briggs-Rauscher oscillating reaction:
From Wikipedia: "The Briggs-Rauscher oscillating reaction is one of a small number of known oscillating chemical reactions. It is especially well suited for demonstration purposes because of its visually striking color changes: the freshly prepared colorless solution slowly turns an amber color, suddenly changing to a very dark blue. This slowly fades to colorless and the process repeats, about ten times in the most popular formulation, before ending as a dark blue liquid smelling strongly of iodine."
You can watch the video on GoogleVideo or on StumbleUpon Video.
The second video is a complete movie - Life after people. If you ever wondered how the world will look like if the human race will just disappear in a second, don't miss this movie. You can watch it on GoogleVideo. It also includes a lot of scenes of collapsing buildings...
I wanted to watch this one for a long time,. and I glad I finally did. It documents the effect of time and the ability of nature to adapt extremely well, in my opinion.