If you make a commitment to do something at a certain time of the day and people are depending on your execution, are you working? You are not employed, but you are committed. Is that retirement? Who knows. But I will be doing something on that order, if/when I actually quit the megacorp.
I will be doing some sort of pro bono engineering work with expenses covered. For example strongly considering Peace Corps, Engineers Without Borders or equivalent organization. Either that or continue to tutor/teach math/physics to inner city kids, or both. I tutor high school kids now and it is a real blast. They are so funny when they find out that the old man from the affluent suburb is on their side. I have about 20 young people who are in or graduated from engineering schools so far. I get an escort from my car to the teaching site and back and I have the sense that folks are watching my car so that it there when I get back. Not unlike working with the Mountanyards back years ago.