On my todo list is to build my own set of network attached speakers. superficially, it does not appear too hard, that is, seemingly possible for even my very limited mechanical integration skills.
BOM: a halfway nice powered speaker with an integral amp and a single board computer. mount the sbc onto the speaker. then use a audio server to ship the sound around. I am a huge obsd fanboy so I would use sndiod but the linux ones(pipewire?) would probably be better for the task.
The main thing stopping me from doing it is that it turns out I dislike dumping sound into the atmosphere, nothing wrong with it, I just don't enjoy blasting music. so I just stick to my headphones, and think about it once in a while.