remember, if you can't open a jar, just hit the corner with a knife as hard as you can to break the seal!

I broke the shit out of my wrist one time. My boss at work dropped off a care package since I couldn't go to work for a little bit (pain killers were fricking up my life). One of the things she left me was some chips and a jar of salsa. With a broken wrist, you can't put any pressure at all on a jar lid, it's not even possible. Somebody on the internet suggested jamming a knife through the lid to let the pressure out. It instantly worked. That's my suggestion if you seriously can't open a jar, just puncture the lid and it comes right off.