Ask HN: Best technical kindle books

I am going to be traveling a lot in the next couple of weeks so I am looking for some new technical books for my kindle. I'm wondering what you have been reading on your kindle and what you would recommend. I just finished reading Building Scalable Websites by Cal Henderson, and Programming Collective Intelligence by Toby Segaran.

I'm open to any suggestions. I don't want to be stuck on a plane flight with nothing good to read.