I had a very similar choice when my phone died. I absolutely will NOT buy a new mac just to manage my phone.
At the same time, my new phone keeps doing its dead-level best to try to force my data up to google. It's starting to piss me off. It's not going to get any more real updates (not going to version 9.0) so I could root it and do whatever I want but still...
You know, I might just do that. There's plenty of things I'd love to do to my phone that would make me happy.
Edit: Psst... you know you can install OSX on a windows laptop, right?
Might have issues with drivers, maybe. I'd check if you can get Mac drivers for those first.
Personally, I use old laptops as emulation systems, for role playing, devices for writing or art. Nothing intensive but nothing I want to buy a new laptop for either.
It's a version of Linux, yes.
My old macbook just died. I'm not spending $2000 on another one but I also don't want to store everything on Google servers. I figure I'll wipe the Chrome off and have a new Linux laptop.