With two very recent natural disasters in mind: the cyclone in Myanmar and the Earthquake in Sichuan, China , the topic of getting pure and drinkable water to needy populations has come back into the conversation. Following, several videos which propose different solutions to supply clean water or at least make it easier for people to have a healthful liquid to drink.
These solutions have the bases covered: well digging and water for maintaining health and hygiene after emergencies, a PlayPump and a Q-Drum roll-able water container to transport the liquid: from underneath the ground and from far away and A Bio-Sand filter and purification bicycle to help make this water they transport, clean and safe for drinking and use.
First, from South Sudan, a Video Journal which speaks about the challenges faced by the Water for Sudan  project in order to build and maintain wells in rural areas of this impoverished area and how it doesn't really matter how hard it is to get started and running, because in the end, it is worth every effort.
Then, from Pakistan, Action Against Hunger  decided to help the communities who had lost absolutely everything to slowly regain their confidence in a better future by including clean water in their plans. The following video from Dogooder.tv :A few projects which make it easy for people to transport water from one area to the next. First, the Q drum  which is a rolling bottle that can be led by a rope. Second, a play pump which pumps water from the underground watershet to a water tank up high while children play and prototype bicycle  that purifies water as it is ridden.
The prototype water purification/transportation bicycle can be seen on minute 1:00.
In the areas of purification we can see the Bio-Sand filter in action, also from Action Against Hunger :
Another similar clay pot filtration product is being promoted by Potters for Peace , who train local artisans to make clay pots which can be used to filter water. Complete instructions to make the pots and filters can be found here . The following video is of Ron Rivera's presentation in Design for the other 90 percent symposium :