After Bill Schweber wrote about cracking open a design book in Go Offline & Crack Open a Design Book, I looked through my bookshelf and came up with a few design books that had influenced me, although, interestingly, were more manufacturers' data and applications books.
We start with the GE Transistor Manual and a typical circuit I made use of. It's a preamp for phono cartridges to raise the signal to line-level. I used this at the college radio station where I volunteered years ago. We actually broadcast, not with an antenna, but onto the AC lines (a.k.a. carrier current), which radiated enough for nearby AM radios to receive. Large portions of the station's electronics were built from this book.
Click on the picture below to launch the slide show of books. I have a few representative circuits from these books shown, although I can't do them justice with these few pictures.
I'll post more of my favorite books in a few days. For now, please let us know about your own favorites (data, application, or other) that you used or still use in your work.