Scrum/Tools

Open Atrium

Open Atrium provides a very good task-tracking tool called "Case Tracker". Case Tracker allows cases to be categorized (bug, feature, or task), assigned, and grouped into projects. Additionally, Case Tracker can send a notification to some or all team members when a case is updated.
Open Atrium is extremely customizable. Because Open Atrium is based on Drupal, it can even be extended with the thousands Drupal modules that already exist.
Like all Development Seed software, Open Atrium is extremely easy to use

Open Atrium's Case Tracker does not allow cases to be assigned to multiple team members. This can cause problems when two or more team members are to collaborate on one task, as only one of them see the task in her list of assigned tasks.
Though Open Atrium is very customizable, many customizations are wiped out whenever the system is upgraded. Though not impossible, building customizations in such a way that they do not interfere with future updates can be difficult and time-consuming.
As a beta product, Open Atrium has several design flaws. The notification system is especially problematic, often allowing users to spam one another unnecessarily.

The bug dependency feature seems very useful. Scrum recognizes that a product cannot be fully defined from the start. As a result, Scrum encourages the team to write basic descriptions of distant requirements and add specific details as they become apparent. The bug dependency tool may allow for this.
- For example, a team building a website might create a user story for login early in the project. Without much information, this story would be fairly high-level, for example "Users should be able to log into the site." Later, the team could add specific details as additional stories -- "Users should be able to log into the site using their email addresses", "Users should be able to log into the site from their mobile devices", etc. These stories could be added as dependencies of the first.
The Songbird team has written a tool named SDPBOT which generates reports from Bugzilla tickets. The team additionally released SDPBOT under an open-source license.

The authors of SDPBOT note that they "made no attempt to make it generic" and that people using the software should "expect to do some work to customize it" for their needs.
SDPBOT does not generate burndown charts from Bugzilla data, and there does not seem to be any other tool which does generate burndown charts.