I have been thinking a bit about the anti-competitive effects of Google's behavior in the email space. It is something I'd like to research further. One inter

I have been thinking a bit about the anti-competitive effects of Google's behavior in the email space. It is something I'd like to research further. One interesting part of the research would be looking at email provider market share over time (or even just a current snapshot). Does anyone have suggestions on how to go about this? My first thought was to use a password breach like Collection #1 to get a distribution of domains used, then query each domain to see which provider they are using or if they are self hosted. But I would certainly appreciate other suggestions!