I had been hoping Rockbox made its way to android someday and I just saw they've released an early build
http://www.rockbox.org/wiki/AndroidPort
Just installed it on my droid incredible and have begun trying it out. Still very much in early form but if this keeps getting worked on it looks very promising. Haven't tried flac on it yet but am pretty excited about this. I want to say it sounds better....but will have to keep comparing.
For anyone who tries it out the interface is a little odd at first - there's a diagram here
http://www.androidpolice.com/2010/08/31/rockbox-for-android-now-semi-functional/
But I would suggest changing the touchscreen mode to "absolute point"
Settings>General Settings>Display>Touchscreen Settings>Touchscreen Mode
which allows you to navigate around by touching the directory listings instead of using the weird virtual 9 button touchpad.







