Apple has gone a long way to making parts that are more "pure", where, for instance, the chassis of new computers is milled from a solid piece of metal that, once removed, can be shredded and reformed with no more difficulty than a drink can. The same goes, in principle, for the glass.
The plastics in most computers are made from an exotic blend of materials and are not easily reprocessed.
What we need more than cardboard computers is standards on how to manufacture products so they can be unmanufactured in the end and rebuilt into other things. The goal here is for 0% loss in the recovery cycle. Anything below 100% is not, by definition, sustainable.
If that sounds impossible, consider that the natural ecosystem in which we all live tends towards a 100% recycling rate. There are very few natural byproducts that do not have a recovery path. For instance, most trees produce enormous amounts of "garbage" in the form of leaves but these are almost immediately recycled.
Given that the natural world has been doing this for literally billions of years, there is much to be learned.
A great book on this subject is Cradle to Cradle (http://www.mcdonough.com/cradle_to_cradle.htm) which proposes radically re-thinking our industrial cycle.