I've yet to slice myself badly with a knife (touch wood). Have had some interesting other mishaps though.
Embedded a woodworking chisel in my palm: word to the wise, when someone points a chisel at you, instinctively putting your hand in the way is a bad idea.
Sliced down to the tendons (thankfully not through them) with the blunt front edge of a tenon saw. . Quite possibly the most annoying injury, ever, as it took ages to repair. Had a bandage on the thumb for 4 weeks, took it off. First fucking time I flexed it, the cut tore open again. Some choice words were said.
Also managed to put a staple through my fingernail and out the other side as a child, when I somehow forgot how to use it.