Here is another concept found on the web. This one only applies to the general Washington area but it shows what can be done.
The Catalogue for Philanthropy: Greater Washington introduces you to the world of smaller, local charities – with budgets below $2 million. Though they comprise about 85% of all nonprofits, the public rarely hears about them because most cannot afford to make themselves heard. Yet dollar-for-dollar, they offer some of the most cost-effective opportunities for philanthropy. If "making a difference" is one of your goals, then excellent smaller charities may be for you.