This news is quite old, dated 25th October 2002, but it is quite interesting. Didn’t know Yahoo! is going to change its scripting language to PHP from a proprietary server-side page language written in C/C++.
Here are some interesting facts about Yahoo! :

» 201 Million Unique Users
» 93 Million Active Registered Users
» More Than 1.5 Billion Page Views A Day
» 4500+ Servers
» 16 Co-Locations
» 74 Properties
» 25 International Sites
» 13 Languages
» 8.1 Million Lines Of Code In C/C++
» 3.0 Million Lines Of Code In Perl
» Open Source Softwares Runs Yahoo! Business

For full information click here, the page is something like PowerPoint presentation, in slides, 41 of them. The slides also contain some history on Yahoo!.