The idea is something I've been discussing with a friend at work. The concept is simple enough, design a belt buckle that when removed can be converted simply into a slingshot. The simplest way I could come up with was to have two halved of the slingshot attached at the top of the fork. This creates an O shape while open but when folded over becomes a U shape with handle. There would likely be indentations on the outside top part of each fork to attach bands wrapped around a steel pin that is housed in the folded slingshot when it is closed, preventing them from being dislodged. The placement of the hinges and where the bands are inserted is the biggest issue I see. I will do my best to upload a sketch some time in the near future. Cheers.