No techie can have a blog without dedicating part of it to technology. These books are either classics or the best of what I've read lately. I buy fewer technical books in paper than I used to thanks in part to the great Safari books service as well as the availability of excellent and afordable digital books.
I truely believe that no business can keep an edge for very long if they don't embark on a process of continuous improvement. In that respect the "Theory of Constraints" (TOC) provides the framework to do i and Lean / Six Sigma the tools. Though I've done my LSS black belt training, these are but a few of the books worth mentioning in this field.
There are thousands of books on Marketing and it's unglamorous Direct Marketing sibling. I've only read a few and I list here my favorite. Those that have really caught my attention. These book might appeal more to the aspiring entrepreneur or to a manager than to a "academic", which is perhaps why I have found them to be so insightful.
Data visualization if one of those topics, aside from economics, which really gets both thinking and talking. In this short section, you can see the books I consider the best on the topic. Of course, I'm no authority on the subject so I might have left out many "classics".