Those sealed clear plastic clam shells you find at grocery stores that contain various products such as cheese balls, salads, sandwiches, berries, etc., kinda scare me.
Sometimes I have to first rip off a plastic strip to unlock them. Then the fun begins. I grasp the tabs, pull as hard as I can, but I can't open them. In the meantime, I'm worried that the food will fly out or the container will cut me. I've been known to wrestle with them, using pliers, knives, and/or screwdrivers. Sometimes the containers get a little mutilated before I pry them open. Hint to NASA: use these connectors for rockets, space shuttles, and whatever; they're the strongest ever invented.
But then, OTOH, if you accidentally bump them or look at them cross eyed, they'll spring open and spill their contents onto the floor.