Information Aesthetics is a marvelous source for interesting images and projects. In the post there with the above image the patterns are generated by mobile phone usage patterns. There are more of the images at the source site for the project. Information Aesthetics explains:
a mobile phone application, freely distributed for Symbian phones, that visualizes personal mobile communication usage patterns. the application sits on the periphery of the machine, monitoring the connectivity through the number & type of calls received, & then subtly displaying those in the form of a generative graphic. “some days will be really colorful & wired, others quieter & more reflective, either way the resulting visuals will always be personal, unrepeatable & unique.”
each new contact (phone number) in a cycle is assigned a color throughout a cycle. a color transparency mirrors the level of a call’s intensity, measured by how long one takes to attend the call. duration. the size of a call symbol, full circles: incoming calls, open circles: outgoing calls, expresses the duration of the call.