From ReactOS

Deskzilla is a Java-based desktop client for Bugzilla bug tracking systems developed by ALM Works. It is very useful for searching and managing the Bug database as the application downloads all bugs to a local database, so it's able to do very fast queries.

The ReactOS Project has a free Deskzilla Pro license for anyone who is interested. It is fully functional, but you can only access the ReactOS Bugzilla with it.

Using Deskzilla with the ReactOS Bugzilla

1. Download and install Deskzilla Pro (not Lite) from almworks.com. It is recommended to use at least Version 1.5.
2. Download the Deskzilla license key for ReactOS from here.
3. Launch Deskzilla and apply the license key file.
   http://www.reactos.org/bugzilla should be selected in the URL box now.
4. If you have a myReactOS account and want to modify bugs with Deskzilla, click on I have an account on this Bugzilla.
   Enter the E-Mail address of your myReactOS account into the Account name (e-mail) box and your myReactOS password in the Password box.
5. Click on Connect to create the connection.