Fine Clonier has updated his Flickr stream to present these finely crafted minifigure wings!
Fine Clonier often deals in custom decals and not minifigure parts, so its uncertain if he created these or if he's sharing the work of another creator.
The wings themselves are fantastic! Obviously custom minifig angels come to mind, but what about a custom Hawkman!
It's also difficult to tell exactly how the wings attach from this picture. It may be that other custom uses for these wings are possible...
(Picture from Fine Clonier's Flickr stream)