Housing multiple classes under one class

I got an application that uses Smarty, ADODB, and some other custom classes. So I have about about 5 objects floating around, and the Smarty object, and another class contains a reference copy of the ADODB object, and I just get that feeling that it can be better. By having one class where they all can share each others data. Is it just a dream? The only way I know how is by making object/objects like $foo->bar->do_something() But that may lead to passing an object to a class, and Ill end up with multiple copies of an object Any insight or examples would be appreciated. Thanks