Having read some of the Book of Swords series and Book of Lost Swords series by Fred Saberhagen (excellent books btw, I recommend them): here are the names of the twelve swords that his books were about, in no particular order:
Shieldbreaker
Woundhealer
Coinspinner
Farslayer
Dragonslicer
Doomgiver
Stonecutter
The Mindsword
Wayfinder
Townsaver
Sightblinder
Soulcutter
Each had a special property, and a weakness or drawback that was associated with that property. With Farslayer, for example, you named the person you wanted dead, and hurled the sword, which unerringly then flew to bury itself in that person's body. However, it stayed there once it killed that person, and if they had any friends with them, and they knew you wanted that guy dead, you could very well find Farslayer coming back to get you. Likewise, Woundhealer healed anyone it touched, but thus was utterly useless as a weapon in combat.
Hope that gives you some ideas!