At a past startup we had many employees organize a grassroots effort to make pay transparent by crowdsourcing a big spreadsheet of engineering salaries. What was found emphasized the disparity between the extremes of the pay distribution.

I think it resulted in better pay for the under-performer (that was pushed up towards the middle of the pay distribution) and worse pay for the top-performer (that was forced down). There were benefits to knowing we were all playing on a level field, but I'm not sure I'm in favor of it now.

I felt like I could be a high performer, and I also had visibility into exactly what I'd be making for the next few years if I stayed there. With that info, I started fielding messages from recruiters who offered to pay 20 and 30k more.