SCALE: Honeywell on Hackerspaces

But there's also the problem of how do you take these "odd" recurrances and add them to your own calendar? Most calendaring apps that I'm aware of don't have a turing-complete recurrance configuration. Every Nth Zday of the month, yes. But these other ideas, not so much.

But maybe:
the 1st Friday, the 2nd Thursday, the 3rd Wednesday, the 4th Tuesday, and the 5th Monday of every month would fit calandering apps well enough. (I'm sure there are oddities in that schedule, depending on what day of the week the month starts on though.)

The problem is quite general though; we all have many things we want to do, and it's essentially impossible to have a schedule that works for everyone.