why hasn't MSFT or YHOO done this yet? As other people have pointed out, they might have. I imagine the reason it isn't successful is the same reason governmen

why hasn't MSFT or YHOO done this yet? As other people have pointed out, they might have. I imagine the reason it isn't successful is the same reason government sponsorship of startups isn't successful - bureaucracies tend to not work very well when it comes to having to often admit mistakes and changing course - sunk costs bias and all that.