In the late 1990s, there was much prognostication about the sub-computer future. It would put leapfrog theory into action, allowing developing economies to catch up with industrialized nations in one generation. But despite all the publicity and investment, usable sub-computers have not become the holy grail. Only the educated middle class has adopted them. The mass of people, especially in the rural and suburban regions of developing economies, have not. The issues extend beyond expense and availability, because no usable technology has been developed for these potential users. We often hear media-friendly examples, like the fisherman who checks the weather forecast on the web. While these stories amuse people at conferences and NGO forums, the truth is that such users are rare. Most of the applications on computers have little utility for a sub-literate mass population.CellBazaar began with a classroom observation that looked at this weakness and the corollary of opportunity. Simply put, the mobile phone has become the ubiquitous computing device in developing countries. The meteoric growth of mobile phone users in emerging economies has superseded all analyst predictions and future scenarios. The mobile phone has replaced the computer as the fastestgrowing technology. Allowing people almost everywhere to stay in touch with family, friends, and customers, and fulfilling myriad other needs, the mobile phone has become the essential technology. In countries like Bangladesh, the adoption curves have been astonishingly rapid, displaying classic "hockey stick" patterns. To take full advantage of this opportunity, we launched the mobile phone based market called CellBazaar in Bangladesh.