I've thought about doing something kind of like this in the past (tying together tons of data on corporations and individuals -- campaign finance, tax and financial info, etc) but concluded that to make it meaningful (rather than looking like a big data dump) would require a collaborative effort approaching that of Wikipedia and abandoned it.

The question is, you know X donated money to Y at a certain date, and Y is on the board of Z Corp, and ... so what? I never could figure out an answer.