Until now, all my books have been relatively independent of each other: there's no reason to believe that one person would buy An Engineer's Guide to Silicon Valley Startups and Independent Cycle Touring at the same time. The topics are very different, and you're unlikely to be in the mood to read one book or the other.
However, folks are likely to want to read Startup Engineering Management right after (or before) An Engineer's Guide to Silicon Valley Startups, so for the first time, I've provide one single page shopping cart where you can buy any (or all) of the books on one page. As a bonus, if you buy $50 worth of books (any 2 books), I'll provide free shipping. Obviously, this only applies to paper books, as electronic copies always have free shipping.
Incidentally, I recently met with both Obvious and PlayMesh to discuss engineering management, and the feedback on the material that we discussed (which all went into the book) has been very positive. There are other reasons to read this book even if you're not going to be a manager, and I'll get into that in the future. Watch this space.