bug is a simple tracking system for console users. It only depends on common Unix commands. Its database format is a text file containing simple tabbed columns which can be even hand-edited. It uses $EDITOR for submitting or editing the issues and for changing states or priorities. It relies on four fixed fields: ID, Priority, State, and Subject. There is also a fifth free-text field for any other information you may want to store about the issue. There is no database locking or notifications, so it's mostly for tracking the user's own issues.
Savane is a Web-based Free Software hosting system, originally based on SourceForge 2.0. It currently includes issue tracking, project and member management, mailing lists, and individual account maintenance. The issue tracking handles bugs, tasks, and support. The issue tracker's fields ware configurable in many ways: mandatory of not, shown to users according to their role in a group, and with transition management.