While I'm posting articles I find amazing here is one about the cellphone and its effects on the third world.
When I was in SA my friend Wil did a documentary about small business entrepreneurs and micro finance (I know that sounds boring but it was actually quite interesting) and one of the things he looked at was the development of cell phone ladies who have a cell phone attached to a car battery that you could pay to make calls from.
Anyway the article is long but totally worth it.