The only reason my cats have nipped at me is while trying to trim their claws. Cats usually give lots of cues they're pissed off before anything happens.
My cat never uses his claws. I don't know what's wrong with him. He just runs around sucker punching and bitch slapping people, than runs away looking smug. I guess I'm grateful, but he's a weird one.
We had a bad windstorm here and I couldnt get home to feed my cat (I had to get my neighbor to do it). So my cat went about 10 hours past her usual food time, not a big deal, she's a fatty.
Anyways, I guess she was mad because after being fed she went and puked in my husband's slipper. I thought it was funny, him not so much.