A real-life example! :D

http://en.wikipedia.org/wiki/Muramasa

The swords forged by the Japanese smith Muramasa were said to be evil weapons that hungered for blood, according to historical interactions of famous Japanese figures.

Also possibly the origin of the legend that samurai swords must draw blood once sheathed.

Does Alistor from Devil May Cry count? It did sorta impale Dante... then again that might be "Defeat Means Friendship" after Dante shrugged it off.