From: christopher@librehacker.com   
      
   Hi, I was wondering what is the cheapest (and hopefully, simple to wire   
   up) way to get an analog square function. I.e., input a voltage x, and   
   get voltage x^2 out. Or x^2/10. Or some reasonable approximation of   
   either of those.   
      
   The standard trick is to feed the voltage into both inputs of a   
   multiplier chip. But even those AD633 chips are tough to afford on my   
   budget (around 20 USD each).   
      
   --   
   Christopher Howard   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)