Chatterprint creates visual and textual fingerprints of one or more instant message conversations. These sorts of visualization techniques are typically used for browsing archives and exposing behavioral patterns. Instead, we are working to build static visualizations that capture a facet of someone's IM identity. Chatterprints will be easy to create and share, communicating someone's interests and style in a concise visual way. Using Chatterprints as a tool, we can explore what makes someone interested in sharing a personal visualization, what people see in other people's personal visualizations, and what kinds of information people are comfortable sharing from their IM histories.