ITT: Old computers you still use for whatever reason.
I'm using an Inspiron 570. I can't afford my next build yet and I'm waiting for Pascal anyway, so I'm stuck with it. Surprisingly enough, it's a tough piece of hardware, for a stock PC from ~2009, and I've been able to push it pretty hard.
Dude, I still use a Pentium 4 box sometimes. I have a netbook running the original model Atom (admittedly, that's only for when I need to directly connect to a router or switch). I threw out a working P3 laptop last year, because I never used it, and nobody wanted it.
Your version of old hardware ain't that old.