Google ran one internally for some time maybe 10 years ago. (Maybe still does, for all I know.) IIRC it was for points, maybe transferable for massage credits o

Google ran one internally for some time maybe 10 years ago. (Maybe still does, for all I know.) IIRC it was for points, maybe transferable for massage credits or something, so no huge economic incentive. I have no idea if it was in any way effective, actionable, or even seen by executives with decision making power. Based on the quantity of discussion on the mailing list I suspect it was mostly used by a pretty small set of people, so I'd have some doubts about its predictive power.