From: gangprobing.alien@ntlworld.com   
      
   "M Philbrook"  wrote in message   
   news:MPG.2ffa03b59f639298989c48@news.eternal-september.org...   
   > In article , no@spam.com says...   
   >>   
   >> See if you had a device which projected some kind of wave like microwaves   
   >> which excited dust particles (or objects in the room), which made them   
   >> vibrate and cause sound.... could that work?   
   >   
   > maybe you want to look up ultrasonic audio or stereo.   
      
   Baked beans tins & bits of string is more his speed.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)