Small picture or photo frames (GU10)

I have a large number of small photo frames with clip fastenings, recycled from an old art project. They are 6 x 4 inches (15 x 10 cms).
The glass fronts and hardboard backs are all in good condition, but some of the little metal clips are rusty.
Can you find a good use for these? I would hate to take them to the tip.