You’re gonna tear your hair out trying to run AI on a laptop that old.
Definitely either a NAS or a media server would be the best.
If you’re into the learning side, like you said a Linux box you don’t have to worry of breaking would be good, or something to do with networking. Maybe some home automation, dashboard, etc…
I agree with the self sustainability.
I started browsing fediverse a bit back, but there wasn’t enough content so I would go back to Reddit (mostly to catch up on news and discussions).
But I’m going to Reddit less and less now as there are more people engaging in fediverse content. I now mostly go back for specific subreddits, but not the general feeds anymore.