Founders at Work (of course) "Best Practices"-type books that cover the tools and technology the startup is using, whether its Textmate, Unix, Subversion, whatever. Becoming more efficient is never a bad thing. I'd also add books on management and dealing with people: - The Art of Speedreading People - Tieger - Behind Closed Doors - Rothman, Derby - The Mythical Man Month - Brooks - Most if not all the books on Joel Spolsky's "MBA Curriculum": http://www.joelonsoftware.com/articles/FogCreekMBACurriculum... (http://www.joelonsoftware.com/articles/FogCreekMBACurriculum.html)
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