The real killer-app for me was just switching to Linux as my base OS. I can leave containers idling while watching YouTube at a cool 27c internally. I'm using a 6-7 year old T460s, but honestly I feel like I could get away with even weaker hardware if I wanted. A Macbook Air running Linux might be a candidate if I didn't need to wait for basic functionality to get reverse-engineered. As-is though, you can count me among the people who doesn't quite need an upgrade yet.