Relational data represent relationships between entities anywhere on the web (e.g. online social networks) or in the physical world (e.g. structure of the protein).
The video is a screencast of RhNav - Rhizome Navigation visualizing the Blogosphere as a 3D graph using the technorati API. www.rafelsberger.at is used as a starting point.
M. Haouach, G. Venturini, and C. Guinot. HT '09: Proceedings of the Twentieth ACM Conference on Hypertext and Hypermedia, New York, NY, USA, ACM, (July 2009)