The Periodic Spiral

As I was reading NY Times Science section today in the bathroom (the only place I bother reading physical newspapers and magazines anymore) I came across a superb explanation of the Periodic Spiral.  As a young nerd, I was fascinated with the periodic chart and – even though I didn’t like chemistry very much (I was a physics guy) – I spent hours staring at it.  I could easily lose an entire day to the Shockwave version of the Periodic Spiral.  Did you know that strontium has a molar mass of 87.62 and that Y (atomic number 39) is yttrium?