I’m a big fan of Symbian and UIQ3, so I was very happy when I found Bergamot.
In their words:
The Bergamot Project produces high quality free and open source software for the Symbian mobile phone platform used by Nokia, Sony Ericsson, Motorola, and Samsung.
Unfortunately:
As the Symbian environment is presently undergoing significant changes, we are shifting the project’s focus from the UIQ user interface towards S60, which will be the basis for the coming Symbian OS.
Still, I’ve been using Escarpod (a podcatcher) under UIQ3, and it works really well.