Edit in JSFiddle

var Person = new Class({
   
    name: null,
    
    initialize: function(name) {
        this.name = name;
        this.element = new Element('div', { 'class': 'person', 'text': name });
    },
    
    toElement: function() {
        return this.element;
    }
    
});

var sean = new Person('Sean');

$(sean).inject(document.body);
$(new Person('Aaron')).inject(document.body);
$(new Person('David')).inject(document.body);

// later...
function highlight(inst) {
    $(inst).addClass('highlight');
}

highlight(sean);

               
               

.person { padding: 5px; }

.highlight { background:#ffd; border:1px solid #aaa; padding:4px; }