Fixing and then using for Alt-process (or inkjet printing), as proposed is a clever way to use it.
BUT there is something that you can do that will take advantage of the silver ON the paper... Use it for Vaseline-portraits...
It goes like that: You take some vaseline and rub it all over the subject's face (cover the face completely), then take a sheet of paper and wrap it around the face, trying to make it touch the largest part of the face possible, without damaging it too much.
Then, you put the paper in a tray with good fresh fix. Then turn the lights on, wash and remove the vaseline. Finally, develop the paper to make the parts that were protected by the vaseline (and were not fixed) darken, fix again and wash as usual. You'll see a strange (but interesting) impression of the face on the paper, white on black.
Using the procedure the other way (first develop, then fix), gives a negative impression of the face, that is black on white.
Since the paper is FB, I am not sure whether all this will work. I cannot be sure whether the vaseline will adhere with the emulsion and will be impossible to remove. I have only seen good results with RC paper, but it's worth trying...