Virtual surround software for Mac / OS X?

[Kanine]

Looking around there seems to be quite a lot of windows based sound cards that have virtual surround etc.  I am looking for something that would work for a macbook pro / mac laptop - ideally software based if possible.  I have seen the Beyer Headzone and think that it's £750 I can't justify now! Cheers

 

[StoneJack]

Creative Omni Surround USB card comes with surround drivers.

 

[Kanine]

Cheers. Does anyone know of anything just software based - or is the consensus that I will need extra hardware?

 

[StoneJack]

Do you mean software which makes any output sound surround? I have not heard about that at all.
VLC can make a sort of surround for movie files, and probably music, it is in their audio settings. 
But to get surround in games and all other types of audio output, you need a chip to do transform stereo into 5.1 or 7.1 surround, which is the type of cards you mention.

 

[NakkiNyan]

You can use the app Hear - http://www.prosofteng.com/products/hear.php 
 
It has some other options too.