mplayer and quasar work very well as a music player. not so much for video.
i'm using the mplayer from
here.
(i messed things up very badly trying to install the angstrom version. I disregarded the advice
to install libraries through apt)
playing mp3s uses about 10% of the cpu. wma uses about 50%.
with audacious it was 50-70 and 90-100 respectively.
coming from a Zodiac, I'm disappointed with the video performance of the Zaurus.
I think that it was better with Cacko/pdaX. Course i have no idea if the bvdd or iwmmx
ever got updated to 2.6 kernel.
will give angstrom version another go, soon. Need to rebuild my pc 1st.