I thought a salary was... you know... the primary thing that separates "a job" from "doing whatever the hell you want". But I guess I'm just not passionate enough to be a slave to other people's enterprises.
I spend a lot of time working on open source. (I never do so at my dayjob.)
The second an open source project demands my time, I shut my computer down and go for a walk. Out of spite, to be truthful. Whatever is wrong, it can wait.
I've rarely ever accepted a request from an employer to stay late to work on something. And when I did, I regretted it later.
I'm passionate by most peoples' standards, and even I wouldn't subject myself to that treatment.
I can't even call people willing to do this masochistic.