Disruptive start-ups
Poor people can, and will, pay for products that fit their lifestyle and needs, that are affordable, and that they recognize as valuable. These three characteristics make them just as much as a customer as you or I. For example, over 85% of the world's farms are smaller than 5 acres. That's about 800 million people worldwide that make their living from small-plot farms, a potentially huge market opportunity - yet there are currently no mainstream small-plot irrigation methods for developing world farmers. Most all irrigation methods on the market are for farms that are so much larger that it doesn't make financial or economic sense for small farmers to purchase.
For a small, innovative start-up that designs a scaleable, affordable small-plot irrigation method for farms of 5 acres or less, their market opportunity is 445 million farms worldwide.
More here: http://bit.ly/pq4Tnw and Vivek Wadhwa here: http://www.businessweek.com/small-business/disruptive-startups-that-dont-get-funded-07282011_page_2.html