I2 is a good system:
i2 Inc. Launches New Version of Flagship Analytical Software To Aid Law Enforcement, Government and Commercial Investigations
Analyst's Notebook 6 Redefines Concept of Link and Timeline Analysis, Promotes Cross-Agency Cooperation to Benefit Analysts and Investigators Around the World
SPRINGFIELD, Va., January 2003 – i2 Inc., the leading worldwide provider of data visualization and link analysis software, has announced Analyst's Notebook 6, a new version of the company's award-winning software which brings clarity to complex investigations and intelligence analysis by uncovering hidden links between seemingly unrelated persons, places and events. Currently more than 1,400 law enforcement, government and commercial organizations in over 80 countries rely on Analyst's Notebook, and it has proven effective in investigations ranging from counterterrorism to organized fraud.
(http://www.i2inc.com/Company/Press/0103b.asp)
However, the system is only as good as its user. Declutter options are nice for identifying key nodes, but the layout may not make sense unless manually organized. Also, once you have the scale you want, if you go to a hard copy you may need a large-scale color printer to print your products. All of which can be very expensive in time and money.