This is a freely available (Creative Commons licensed) calculus book, covering a fairly standard course sequence: single variable calculus, infinite series, and multivariable calculus. It is also available in a late transcendentals version. As of the 2011 version, there is a differential equations chapter, and new in the 2012 version is a section on numerical integration. The 2013 and 2014 versions are largely unchanged, but as of 2013 the book is now available online with some interactive content at Whitman Calculus Online.
The book has been used by some instructors at Whitman College every year since 2006. It also has been used at UC Riverside, University of Kentucky, Northern Arizona, Westmont College, Manhattanville College, Whittier College, UNC Asheville, and Western Connecticut State (in a customized version). I am aware of one review of the text, at the MAA reviews site.
Corrections, suggestions and contributions are welcome. I especially would appreciate donations of exercises and solutions to exercises, preferably as TeX or LaTeX source.
If you use the text for a course you teach, please do let me know.