Have you ever been in a hackspace? That's where you'll usually find such discussions IRL.

Other examples include "let's build a submarine" https://media.ccc.de/v/37c3-11828-how_to_build_a_submarine_a..., creating your own 2000s style phone ringtone/wallpaper subscription service https://blamba.de/ or running toslink audio over regular long-distance fiber links https://blog.benjojo.co.uk/post/sfp-experiment-ultra-long-ra...