One of Sunlight's resident creative geniuses (yes, there are many of them) have taken all the Defense Appropriations Earmarks and made them available for viewing within Google Earth. (You can only view this using Google Earth which you can download from this page.)I think we could apply a similar idea to a whole host of state budgets, company budgets (where you could analyze the amounts assigned per departments), nonprofits organizations, etc. Lots of ideas here.
I really prefer visual images that describe information; Tufte's books on visual design should be required reading for everyone, in my opinion.