Wordpress how to display a different page for mobile

Essential what I'd like to do is to show a different landing page when a user arrives from a mobile device.  The only thing is I can't seem to find a plugin that does just that.  Most mobile plugins are designed to change themes and not just the static page. 

Rather than make the needed plugin what I'm going to do is use some CSS tricks to display the content I want on mobiles and not on larger screens.

So in concept you have something like

@media handheld, only screen and (max-width: 649px)  {
.largecontent { display:none; }
}
@media handheld, only screen and (min-width: 650px)  {
.mobilecontent {display:none;
}