The Traveling Wizard is a man of minor repute. He has made great impacts on a few places and people. Those that know him, know him to be powerful. However, most do not know him, for he travels the world. He seeks experience and knowledge, craves adventure. The journeys of the Traveling Wizard seem to never end.
The creation of intelligent magical weapons is not an exact science and there are occasional failures, as such think of causing a little more stress to your players by "rewarding" them with an insane magical weapon
Agrophobic, refuses to come out of the scabbard without a strength check to draw it.
Haemaphobic: afraid of blood, fight at a penalty against any blooded creatures but really good against undead, elementals etc
Schizophrenic, not just one mind in your sword, lets have half a dozen minds in there, all different and bound to cause confusion
the possibilities are endless