It's not a direct line, but you'll get to the admin secretary closest to Steve Ballmer. If you have a longstanding Microsoft issue that multiple trips to the MS customer service line haven't solved, try pitching her your problems. Microsoft Steve Ballmer
Tired of searching my “sent mail” for every great idea, interesting article and new study that I forwarded to one random colleague or another in hopes of lending some inspiration, or at least creating an archive for myself, I decided to give in and ad