History of Zero: A really fun book I read! (Score 2, Informative)

I'm a HS Math teacher myself and I once read a book called 'A History Of Zero'. It was pretty fascinating. It didn't deal with a lot of higher math, but had some really interesting stuff about the number which is zero. Check it out here: http://www.amazon.com/Nothing-that-Natural-History-Zero/dp/0195142373