Solar power systems with integrated GSM connectivity build in to enable financing are also taking off with a huge amount of investment being made into companies providing these such as BBOXX, Mobisol and M-Kopa.
What I really like is that most of these technologies are not just being transferred from the Western world, they are technologies developed for the context and bypass the outdated technologies used elsewhere. Even more importantly they are being developed to be commercially viable and not dependent on aid money or donor funding.