jquery.or.js

// jQuery.fn.or
// 
// $('.dont-exist').or('.does-exist') //=> [.does-exist];
// $('.does-exist').or('.dont-exist') //=> [.does-exist];

$.fn.extend({
    or: function(selector, context) {
      if ($(this).length > 0) {
        return $(this);
      } else {
        context = context || $(this).context;
        return $(selector, context);
      }
    }
});