A typical electronic logbook is designed as a general-purpose system for recording time-ordered events and actions and, therefore, allows for a great flexibility in recoding information, but the data is unstructured. To better position it in a specific context (e.g., a controlled system, test facility, group activity log) one needs to add some structured information and allow for unstructured data (text, title, attachments, entry attributes) to be put in that context. To do it a logbook system can define a set of categories, possibly built as a hierarchy. These application-specific categories will be associated with each entry. To remain flexible such a system has to be configurable to allow for tailoring it to each specific environment. The paper describes a design, functionality, and experiences with WebLog, a database-configurable electronic logbook developed with the J2EE Web technology. Various functional and technical properties of the system are discussed, including multi-category based queries, text searches, threads of entries, an automated alerting system as well as integration with other applications via Java, C/C++ and LabVIEW gateways, and multi-log installations.