Hi, I'm sure I've seen a site indexing interesting information about the technologies under major sites (google, yahoo, facebook, stackoverflow itself and so on), indicating what server they run on, what programming languages and database are used and so on.
Can anyone help gathering any information? Thanks
Stack Overflow is primarily built with C# and other Microsoft products.
This might be what you are looking for: http://highscalability.com/
Some of the sites being covered:
Most sites, especially the ones which are built using free software have banners telling you what backend they use. I'm sure you saw things like "Powered by Apache/Php/Mysql". This is a nice way to give credit.
Also, many web frameworks, webservers, database engines etc have a section on their site that lists who uses them. For example, load http://rubyonrails.org/ and scroll down a bit.