Comment Charity: Water gives 100% (Score 5, Informative) 570
I give to Charity: Water. They've got a great proposition where 100% of your donations go directly to the field to fund water projects. They're also a tech saavy group of folks and try to prove that by providing GPS signals and photos of the project you funded. Administrative costs are covered separately by a group of benefactors (who understand they are solely paying for administrative costs).