Photo: Microsoft, Novell shake hands on Linux

Why are these CEOs smiling? In San Francisco on Thursday, Novell's Ron Hovsepian (left) and Microsoft's Steve Ballmer unveiled an unexpected collaboration between their companies to address longstanding corporate concerns over the role of open-source software. The software makers say they'll work to help bridge the technological and business divide between Novell's open-source Suse Linux operating system and the proprietary Microsoft Windows.

Photo by Microsoft