Several -- perhaps 15 -- years ago, my friend Marco recommend a book to me called The Complete Bolo . He loaned me his copy, which I immediately read and loved. (Marco is himself an author of articles on C++ and Object-Oriented programming. You can read his stuff in old editions of Ziff-Davis magazines.) Books one thru four are listed under Keith Laumer in the book store, but he didn't author any of these newer stories. The new stories, however, are, for the most part, every bit as enjoyable as the original book. Book 4 includes stories by David Weber, S. M. Stirling, and William H. Keith, Jr.
Bolos are semi-autonomous tanks (the military kind) that are controlled by an artificial intelligence. Their loyalty is to humanity and to their duty - to obey orders and to defend humanity. They are fearless, loyal, tenacious, meticulous, and will fight until utterly destroyed. [Interesting aside: I've been told by a military person that the term 'bolo' means 'loser' in army slang. A very curious term.] All four of the later books, as well as the original Complete Bolo are a collection of short stories about the activities of some of the machines - very similar to Isaac Asimov's I, Robot , which one immmiately thinks about while reading this series. Another series of books that comes to mind is Saberhagen's Berzerker Saga, some of which are collections of short stories, and others of which are complete novels. (Warning: The Saberhagen novels are religious propaganda! Think Chronicles of Narnia or A Canticle for Liebowitz .)
The stories are sometimes humorous, sometimes uplifting, but very frequently tragic and depressing. The natural evolution of the machines is that they eventually develop true human-like emotions and become, in some sense, superior to their creators. My particular favorites in this final (gee, I hope not) book are "The Traitor," "Hold until Relieved," and "Don't Come Back." Very entertaining.