Cyricx is right Erwin, it ain't there.
I'm not talking about the disable vbcode (which disables smilies too), as that only disables the box. Doesn't stop people seeing the smilies others insert into their posts.
In the Invision board Options panel, where you select to have Avatars and Sigs enabled/disabled, it also gives the option to turn smilies on or off. If disabled then all you'll ever see is the code and not the actual smilies, just as you don't see avatars or sigs if they are disabled.
That's the only thing I envied the Invision board for.