Engineering firms have commonly done 4x 9 hour days with the remainder (to hit 40) either half day Friday or alternating Friday's off. I've always enjoyed it.

Engineering firms have commonly done 4x 9 hour days with the remainder (to hit 40) either half day Friday or alternating Friday's off. I've always enjoyed it. Plus it makes adjustments easier and feel less burdensome - where if you need to take a few hours off during the week, it's easy to stay a bit later on Friday's without working past normal business hours. And you don't feel overworked by Thursday night, as the guy interviewed said after doing 4x 10s.