i have gloves that i wear to do water changes. my 13" midas still bites me with them on and it gives a good pinch. he bit me once without the glove and it bled badly. it scared the crap out of me more than it hurt!!
I've had little fish nibble on me, guppies, mollies, that sort of thing.
But my crabs and lobsters pinch me, they are small so it don't hurt. Sometimes i let the crabs crawl on my arms out of the tank. give them a little bit of freedom when i can...
Older thread, but I saw this and got a good laugh at the bottle of Advil in the background. You were supposed to describe how the bite felt, but the blood and the Advil says it all. Ouch!