WikiScanner, developed by California Institute of Technology graduate student Virgil Griffith, traces the IP addresses that get stored when anonymous editors make their changes to Wikipedia articles and links them back to the organizations they came from. So, if U.S. Senate staff members were to repeat the editing efforts they undertook last year to remove information that made certain senators look bad, for example, everyone would know it.

This is an awesome way to data mine already available data (due to Wikipedia's open processes) and mash it up. This list of Fox's changes to Wikipedia is pretty interesting.