Couldn't I do a variant of my effective arrows only like effective swords? Think it would do everything that's really necessary. Also me doing it my way would mean it would be done within like 40 mins of me starting it! EDIT by Moderator: merged posts, please use the edit button instead of double posting.
you you could but i kinda don't want the effects to already be there, they have to be gained somehow....
Here's an idea: Maybe make it so they have to make a base offering of so many items to use it and then it would have an interface similar to my effective arrows. So say u have to sacrifice a flint and steel to use a fire sword and each use requires some type of item.
Enchantments. And from there I hope bukkit makes the enchantment API available for custom ones (depends on how Notch did it).