This is a terrific article alluding to the possibility of a conflict of interest between Bill Gates’ manufacturing empire of software and his latter-day interest in Education:  http://voices.washingtonpost.com/answer-sheet/teachers/bill-gates-troubling-involveme.html

To test the appearance of impropriety we could outlaw the use of public funds for any microsoft product, whether soft- or hardware.  Were the Gates’ Foundation interest purely focused on improving the educational lot of our nations’ children, this should not alter the devotion of its funds toward this end.  If instead there is a common cause in also selling their own software (over and over) to the small private schools they have shoehorned into our public school system, perhaps with this restriction we will see a lessening of Gates Foundation interest in the public schools?