well, currently we can't see farther than the observable universe (obviously, thus why it's observable), so the real answer is "we don't know", however, I would assume it's likely just more empty space. There are, however, many neat guesses about this, though none of them can really be proven (we will never really be able to observe the unobservable universe, though im sure some day we might be able to figure it out). Some theories state that it's actually circular, and if you pass beyond the edge, you find yourself on the other "far side" of the universe, while others subscribe to a multi-verse theory, and once you expand beyone our little "bubble" universe, you would find yourself in another bubble universe (though the method moving between the two wouldn't exactly be clear)
As far as your previous question, i see what you were getting more at now (i think i took your question the wrong way previously, and it didn't make much sense to me, but it makes much more now with this clarification), and it's actually a very interesting subject with, unfortunately, no answer in the foreseeable future.