It's a big book indeed: at 432 pages, it is wider and thicker than many of the other books on my shelf, and it is filled with dashboards. I've been recommending The Big Book of Dashboards regularly at my workshops since its publication in April of this year, and am overdue on my official endorsement of it here. If you build dashboards, you should own this book.
When creating a dashboard, if you've found yourself wondering, What would be a really good way to show this?—you will find a number of inspiring potential answers to that question in Wexler, Shaffer, and Cotgreave's book. The meat of the tome is Part II, where they present 28 dashboards from various industries on a wide-ranging set of topics. In each chapter, they introduce the full dashboard, briefly discuss the business scenario, then break the dashboard into its component pieces with commentary on both what works well and what they might have done differently. You will find inspiration here. This is enveloped by Part I on the front-end, which covers some data visualization basics, and Part III on the back-end, which covers real-world challenges the authors have faced in their combined 30+ years of working with dashboards and ideas for overcoming these challenges.
In addition to buying the book, I recommend checking out the companion site (where you can find additional resources, including many of the actual dashboards featured in the book) and following the authors' work: Steve, Jeff, and Andy. Nice work, guys!