What's the oldest piece of tech you still have running?

Are you keeping up with the Commodore?

My dad was showing us all Moon Shuttle for the 64, some old game he'd never played. And then he pulled out a chip he called "the shadow" that I guess has a history to it. It was a replacement for another chip you'd plug it into the hard drive to... Copy games? But they didn't work or they didn't make enough? He even showed me his thermal printed complaint letter he wrote explaining how long he waited and how many times he was fobbed off.