Someone sent me this link, its interesting to say the least
A fascinating discussion ensued, George Ou went off to research the concept and, at the risk of spoiling the surprise, here is the result in George's fine words:
"I recorded a sound file that would engage speech command on Vista, then engaged the start button, and then I asked for the command prompt. When I played back the sound file with the speakers turned up loud, it actually engaged the speech command system and fired up the start menu. I had to try a few more times to get the audio recording quality high enough to get the exact commands I wanted but the shocking thing is that it worked!"