Going to give a wide range of answers based on topic, so you can pick up what interests you. Happy to give more if none of these appeal to you.
If you work in tech, Stafford Beer’s Designing Freedom. It’s very short, accessible, and full of so many big ideas about what computers are for that it exposes the tech industry’s absolute fucking poverty of vision.
If you’re interested in deep dives on more technical topics, David Graeber’s Debt. It’s a fucking tome, but it’s also amazing. So much of what we take for granted in our world is completely arbitrary and made up, but no less powerful, and there’s nothing quite as arbitrary and powerful as the concept of debt.
If reading a cinder block based on an internet stranger’s recommendation is too much for you, maybe try Graeber’s Fragments of an Anarchist Anthropology, or his The Utopia of Rules instead, depending on which topic interests you more. Graeber is a great place to start because he’s accessible but also his mind isn’t limited by the confines of capitalist realism in a very special way. He was truly one of our best.
If you want something that’s extremely light and fiction, I recommend William Morris’s News from Nowhere. It’s extremely cringe in a way that only 100-year-old socialist utopian fiction could be. It’s excessively sincere, even naive, in a way that rings hollow to our cynical modern selves, but it’s such a short read, and it’s so adorable. I like the way that he challenges the concept of work. I think that the modern left should revive that line of criticism. I also enjoyed that you can see early versions of things that we associate with more modern movements in his utopian vision, especially degrowth and reforestation/environmentalism, not just for “the environment,” but with nature as a part of and inseparable from the human experience.
Finally, if you like philosophy, and you want in depth analyses of capitalism, and don’t mind something that’s maybe less accessible, I recommend Adorno and Horkheimer’s essay The Culture Industry. It was written in the 1940s, and it reads prescient today. They saw the rise of capitalist mass media as more than just a threat to independent thought, but a pacifying, homogenizing, almost all-consuming force. If you want something longer than The Culture Industry, and probably slightly less accessible, I recommend their Frankfurt School colleague Herbert Marcuse’s One Dimensional Man. He basically argues that capitalism, and more specifically what he calls “technical rationality,” has conquered our culture and our very ability to reason, at scales big and small.