GPFM - it is a file manager that plays mp3s - and is more useful than wind-ups in my opinion(but hey thats just my opinion)
and there is a guy I spoke to on #gp32dev who is infact developing one which is incorporating better tags(id3 I think) with playlists - better functionality etc - but do not quote me on this as this was a passing conversation. Whether it gets released is a different matter. --This guy had some really good ideas..