Just as an exercise I ripped the progress bar rendering code out of MPlayer and generalized it, fixing some 10 to 15 bugs in the process. Though I couldn't get it back into the MPlayer source (yet!) its already going into other software, most notably Senuti. So if you need such a progressbar, have phun!
As I'm still gearing up on my graphics programming, there is still the unesthetic choice in there to use pictures for some of the interface elements. So, free after Wil Shipley thats a no no. :) If you (the reader) care and could send me a patch, that would be greatly appreciated.