I'm one of those people who read more than one book at a time. Currently, I'm reading The Definitive Book of Handwriting Analysis because handwriting fascinates me, as well as Dying to Win: The Strategic Logic of Suicide Terrorism because suicide and terrorism are also fascinating. The first one is pretty cool, I've been using it to help me understand/develop different ways of writing in Elian Script, something I am deeply fond of. Elian script emphasizes creativity and expression in developing your own unique version of the script. Studying graphology helps me figure out what I want my writing to portray. The second book is really just more of a filler. I'm not as passionate about suicide terrorism as I am about writing. It has been pretty informative though, it certainly makes a lot of what's happening in the Middle East make more sense.
Man, if I had the money I'd pick up The Definitive Book of Handwriting Analysis. Back in high school, I became really interested in the criminal mind and all the ways the criminal justice system worked. I borrowed every book in my town's small library that had to do with criminal cases, law, criminal profiling, and the one book on handwriting analysis. It's some really interesting stuff.