The following is not honestly directly related to this article, but an occasion for a developper to inform you about a software I created that is directly related to your field of concern. It's a new concept about barter where people make bids and where best compromise between them are automatically found. It allows economic exchanges without the need of money and could really help countries where economy is paralyzed by the lack of financial ressources. The tool proves if is possible to build such a search engine, and works fine, but you will see it cannot be used practically yet. I have ideas on the next step that would make it economically usable. You can visit http://www.openbarter.net or email me on olivier.chaussavoine@laposte.net if you want to know more on the subject.