tronics

Not many trackers support the multiple project support.

If you are no ruby developer the stacks from bitnami are recommended to get this running: bitnami.org/stack/redmine

Clean and wisely built. Good structure and very, very lightweight.

Very powerful framework. Needs some time to understand but from there it is a breeze to use.
Relies on code generation instead of Active Record - therefore searchable sourcecode instead of magic.
Another feature is that Developers can concentrate on the business logic.

The spinoff qcubed http://qcu.be/ is even more interesting as it uses JQuery and contains hundreds of bug fixes.

Awesome tool. Never let me down. Eecommended.

One pun: Lately it uses advertising in the installer.