Microsoft CEO Steve Ballmer insinuated that the company is working on a version of Office for the iPad and for Android tablets when he addressed Wall Street analysts on Thursday. Speaking about "upside opportunities" that exist for Microsoft, Ballmer talked about porting products to non-Windows platforms. "We don't have our heads in the sand," he said during the company's meeting with financial analysts, which was held in a Bellevue, Washington convention center and webcast live.