I tried to take the batteries out of my cordless keyboard, and they were stuck so i tried to pry them out with my pocket knife and it slipped. I am now a victim of a vicious painful cut on my right index finger!!
I think i'm even dripping blood into my keyboard as i type this!! Even MORE evidence to help me win a lawsuit!!!

Should I sue the keyboard maker, the battery maker, or the knife maker?
It's their fault for making the batteries so hard to take out, right?

It's your fault actually. You can't sue for this, it's just plain stupid that you would try to take batteries out with a knife.