The Light Of Other Days by Arthur C. Clarke & Stephen Baxter
The scientific theme of The Light Of Other Days is the development of and further evolution of technology using wormholes. To my way of thinking, the earlier stages with monstrously large equipment and power to maintain narrow wormholes was far more credible than the only-a-few-years-later development of small, portable and affordable devices with less narrow wormholes. Nevertheless, it is not just a story about wormholes, but also about the metamorphosis and advancement of a technology once the ball gets rolling. And it is also a look at how corporate culture and driven businessmen influence this.
Initially, Hiram Pattersons's company develops narrow wormhole only capable of sending electronic transmissions. This can provide highly secure communications or give a tiny time advantage over satellite communications for those in highly time-sensitive work. But once one form of the technology is available, other potentials are explored. Soon, a way to widen the wormholes is found, allowing light to travel through. With that Wormcams, wormholes used to spy on or otherwise observe anyone anywhere, come into being. And from there further more fantasy-like applications: looking into the past, mind-to-mind communication, etc.
At least as presented in the book, it's a technology with huge, broad and varied potentials. It is technology that changes the world as we know it (well, at least in some regards). The book shows us that process unfolding.
One subplot is storybook-like in that those manipulated into making the technology what it is use the technology to learn secrets of the manipulator.
Another subplot involves issues around the knowledge a huge asteroid is going to hit the Earth in 500 years.
Reader interested in issues of feasibility of the kind of wormholes described in this book may want to see the article elsewhere in this site on wormholes.