Another idea to keep in mind: the success of the web 2.0, in economical terms, is the equation “low instalment plus a lot of people equals a lot of money”. See examples like Flickr or Last.fm, that ask you for a small amount of money, to get a benefit based in the incredible amount of subscribers.
So, with these two ideas, I wonder why tech companies don’t look at the 3rd world as a possible market. Maybe they can’t pay 300 euros for a product, but maybe they can spend a small amount of money to increase their well-being… and there are millions of people in this situation. Maybe the reason is that this adventure is too risky… but “no risk, no return”.