For open-ended information tasks, users must sift through many potentially relevant documents, a practice we refer to as document triage. Normally, people perform triage using multiple applications in concert: a search engine interface presents lists of potentially relevant documents; a document reader displays their contents; and a third tool - a text editor or personal information management application is used to record notes and assessments. To support document triage, we have developed an extensible multi-application architecture that initially includes an information workspace and a document reader. An Interest Profile Manager infers users' interests from their interactions with the triage applications, coupled with the characteristics of the documents they are interacting with. The resulting interest profile is used to generate visualizations that direct users' attention to documents or parts of documents that match their inferred interests. The novelty of our approach lies in the aggregation of activity records across applications to generate fine-grained models of user interest.