I was contacted recently by WorldWater, a company making solar-powered irrigation and water supply technology, to let us know that they have been asked to supply water pumps for irrigation and purification projects in Sri Lanka, as part of the post-tsunami reconstruction effort. WorldWater has active projects in California as well as in East Africa, the Philippines and (pre-tsunami) Sri Lanka. It looks to be pretty straightforward photovoltaic-powered pump technology, but they definitely seem like a company worth knowing about.