Our friend Keir is preparing for his next movie and writes:
...though my energy canon and nuclear bomb are not quite finished ( I will send you pictures when they are) I have another prop that may interest you.
Upon looking at the first picture it looks like a cool, sophisticated crossbow. However, it is just a thrown-together prop which barely needs to work and I only put together for a few scenes. It does function however and its firing mechanism is: yes, a binder clip.
So there is another use for binder clips for you: "Crossbow Firing Mechanism"