I can create a weapon that gives the character a skill, but I'd rather have the weapon just randomly use the skill instead of the player having to select it.
E.x. :
A sword of fire
randomly on hit (during battle) the sword would use skill x
Skill x = fire damage spell of Z damage.
Much like a 'weapon proc' of modern day mmorpgs.
Having the 'random on hit' be a changeable modifier would be extra awesome.
I think having a weapon that will randomly use a skill or 'cast a spell' in this case, would add much flavor to choosing the right weapon for the job