Holy crap.
Yahoo allows outsiders to innovate on Yahoo e-mail – Sep. 30, 2006
Officials of the world’s largest Internet media company said on Friday it planned to give away the underlying code to Yahoo Mail, one of the crown jewels of its business, in a bid to encourage software developers to build new applications based on e-mail.
The move to open up the underlying code of Yahoo Mail — used by 257 million people — is designed to spark development of thousands of new e-mail applications built not only by Yahoo (Charts) engineers but by outside companies and individuals.
These people have guts.