My first thought involves a Monopoly-like game board as the standard controls and background.
Color coded arrows indicate to where and from where money would go. ie if you searched a senator then his pic would pop up in the middle of the screen surrounded by inward and outward pointing arrows. To each arrow you can attach a thread among the other usual ways to find a thread topic.
This would also be done with agencies, grants, programs ect…
I would add a section that allows viewers to suggest and vote on ideas to develop it (idea stolen from Ubuntu Brainstorm)
The biggie is how to get people to participate in adding new arrows (money paths). Get the community involved in developing the site so that my role is verifying info more so than finding it.
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