For those unfamiliar with Wikis, they are a tool for creating collaborative web-based documents that are constantly changing through contributions from a wide group of users. The most famous Wiki is the wikipedia, the online contributory encyclopedia, but they are used internally at organizations to exchange ideas, document changes, and a variety of other tasks.
But, how does your wiki grow? IBM wanted to know, so they embarked on a project called History Flow Visualization, which creates a visual description of a wiki's page growth over time.
I haven't used the software yet, but it looks like an interesting application of graphics visualization technology to textual information processing, with wikis as a ripe target. Because of their dynamic nature and potentially explosive growth, they are not only an interesting subject, but provide an opportunity to see pretty graphs.
The software is Java based and runs on any Mac, Unix and PC platforms with 1.4 of J2SE installed (10.3.x Macintoshes will have this, for all others, check your versions).