Not even as a side project or something though, running on some old hardware you were never going to use again? I guess this whole thread is about working environments and precisely not what we play around with in our spare time though.

To be honest, I hadn't really given much thought to my OS for even longer before I decided to go looking myself, I'm glad I picked that fight though. Granted, 8 years ago I was 15, digging in to the guts of an OS for the first time is very different from focusing your time to build what needs building :)