Ever heard of product space? It's one of the new frontiers in the field of international trade and economics spearheaded by Ricardo Hausmann, Cesar Hidalgo, Bailey Klinger, and Albert Laszlo-Barabasi. It basically tries to map a country's endowments and technology, and shows where the country's comparative advantage lie (in terms of products) and where the country is currently situated in vis-a-vis its comparative advantage. One very interesting finding is that based on this new form of analysis, they find that the way countries develop comparative advantage is far from random, and that there might exist a lack of convergence in international income levels given the structure of the product space. Still developing countries might find themselves in the outer periphery of the product space with few opportunities for diversification, whereas other better-off countries find themselves near the central core of the product space and have developed capabilities easily deployable in a wide range of products, creating a path to convergence.
Wikipedia's entry on Ricardo Hausmann provides a simple analogy that would give you a picture of what product space is:
"Think of a product as a tree and the set of all products as a forest. A country is composed of a collection of firms, i.e., of monkeys that live on different trees and exploit those products. The process of growth impliesmoving froma poorer part of the forest, where trees have little fruit, to better parts of the forest. This implies that monkeys would have to jump distances, that is, redeploy (human, physical, and institutional) capital toward goods that are different from those currently under production. Traditional growth theory assumes there is always a tree within reach; hence, the structure of this forest is unimportant. However, if this forest is heterogeneous, with some dense areas and other more-deserted ones, and if monkeys can jump only limited distances, then monkeys may be unable to move through the forest. If this is the case, the structure of this space and a country’s orientation within it become of great importance to the development of countries."
It's actually a very exciting and interesting new field, and it surprisingly has economic sense. Too bad though, as Niny Khor of the Asian Development Bank mentioned, much still needs to be done in terms of its theoretical foundation. But the fact that it is built upon the basic models of international trade, it won't be long before a firm and strong theory will come out and support the product space field.
In the meantime, you can check Cesar Hidalgo's excellent website for a snapshot of what a country's product space would look like...as well as his other materials on this subject.