Edward Tufte, in his much loved The Visual Display of Quantitative Information, lays out a clean approach to data graphics and visualization. By thinking carefully about representing the data and analysis with context and the efficient use of “ink”, a graphic has a better chance of telling the real story.
An example that caught my eye a while back is Norse’s live cyber attack map. Notice the heat map that builds up as time progresses, a visual representation of the aggregating tables beneath. I find it much more informative than the dramatic exploding circles that emanate from both attackers and targets.