Brad Bird's Ray Gunn has been in and out of development for well over a decade now. For a while in the mid-90s, it was set up at Warner Bros. but they, foolishly, decided not to press ahead with it.
The Pixar Room site are playing host to a small piece on the film. I'd recommend you head over to check it out. No idea if you'll need a little help to read it, but I promise - it's worth the effort if you're new to the whole Ray Gunn story. It's definitely a nice place to begin exploring this delicious-looking lost classic.
The pics above (click on them to make them bigger) were all drafted by Sylvain Despretz. A couple of the images - which appear on the artist's Flash-heavy site - were meant as environment designs, but those without environments were, obviously, early character designs. Before development was over at Warners, the look had evolved somewhat, but this is the best we have in the public domain for now. The lady with the white hair is Venus and, reportedly, she was much more striking and classically beautiful when designer Tony Fucile took a pass at designing her.
There's every possibility that some kind of Ray Gunn film will make it out into reality, eventually. First of all, however, Bird has Ratatouille to polish off entirely, then his untitled, rather secret, live action film to make.