I know of a husband/wife surgeon team who split their practice and call. Part time work is actually not too hard to arrange once you’re done with training. Easy, in fact, in many specialties. My colleagues moonlight in emergency departments fairly often. You can make around 3K over a weekend of straight call (48+ straight hours). That would be 50K/year for working one weekend a month!
It’s the residency that kills you. I’ve heard rumors of residencies which allow 2 people to share a position, usually in Peds or Family Practice, but have never talked to anyone who has actually done it.