In Dr. Strangelove (1964), the USSR builds a Doomsday Machine to function as a credible deterrent to a nuclear first strike against them, but keeps it secret. Dr. Strangelove famously remarks:

The whole point of the doomsday machine is lost... if you keep it a secret! Why didn't you tell the world, eh?!

The USSR actually built such a system and kept it secret.

This website is great for all things science fiction. Here's a list of technologies that were predicted (there are hundreds!):

http://www.technovelgy.com/ct/ctnlistalpha.asp 

H.G. Wells' The World Set Free:

More than 30 years before the first atomic bombs were made, H.G. Wells’ 1914 novel, “The World Set Free,” depicted a war where atomic energy fueled powerful explosives. Inspired by the potential applications of new scientific discoveries, science fiction authors like Wells imagine possible future outcomes stemming from today’s cutting-edge technologies. While many of these ideas don’t come to pass, sometimes–as in “World Set Free”–these futures are surprisingly close to reality.

There might be some examples here.

Linch commented this below, but I think Karel Čapek’s 1936 science fiction satire The War with the Newts  not-quite-predicted AGI and many aspects of WWII (the book portrays things that are eerily similar in style but different in form -- and is generally just insightful). 

Neuralink, and the Culture series also has voice-activated assistants that are a bit like Alexa