Ah you guys are missing the point.
What is the point? You can very well have a "use activated" ability on a weapon. ie- a weapon that shoots fireballs everytime you swing it.
Oh, interesting idea, no?
6th level spell (hieghtened fireball). 11th level caster (10d6=60).
Stick this on a bow. Everytime the bow shoots an arrow, a fireball explodes where the arrow hit.
The killer part? The cheap ass cost. 172K gold. (oh think of the applications if you were epic!)
What? Dont have that type of cash in your campaign?
Remember that silly magic missile spell?
1d4+1 ( 3.5 dmg/hit) = $2K
2d4+2 ( 7.0 dmg/hit) = $6K
3d4+3 (10.5 dmg/hit) = $10K
4d4+4 (14.0 dmg/hit) = $14K
5d4+5 (17.5 dmg/hit) = $18K
Oh yeah.
(so what, your DM made you check for spell resistance? bah!)
~Chris.