A few times. The one I regretted the most was the last year of my career in game development. We were asked to work the weekend once to get some features done. That turned into two weekends in a row turned into a full year of non-stop crunch. Programmers these days like to say how they're so "burned out" because they don't like the work. I was so burned out that I was mainlining energy drinks to stay awake. I developed adrenal fatigue. I still fell asleep in meetings. I have almost no memories from that year. I was a zombie.

The worst part is that it didn't matter. The game was so far off the rails that it never shipped. They closed down the studio soon after. They closed most of the company's offices with a year of the studio closing. 2-3 years after that, the company was completely defunct.

No employer has ever asked me to work that hard again. I would quit on the spot if they did. Life's too short.