Been doing this software thing for 35 years so I guess that makes me an old timer.

Technical books, especially for practitioners, that stay relevant over a long period of time are rather rare. I wish I could say that I've had time to study TAoCP or SICP, but I haven't.

Some of what I did find useful back in the day were: Advanced Programming in the Unix Environment by Stevens, Stan Lippman's C++ book, Code Complete by Steve McConnell, the GoF Design Patterns book, Working Effectively With Legacy Code by Michael Feathers, and Introduction to Artificial Intelligence by Charniak and McDermott.

Whether, and to what extent, any of them are useful now is hard to say. Depends what you want to learn and what you're doing. The Charniak book, for example, is about classic "good old fashioned" AI, not the currently dominant connectionist approach. But it's LISP, and LISP is always relevant.

I'd also add The Systems Bible by John Gall as a book that influenced me. Its not a technology book though.