Erm, depending on the actual rules you are playing: you probably need Quickdraw if you intend to throw more than one object a round.

Also: best in what context ?

In terms of cost: it's hard to beat rocks, since they are free and you are not guaranteed to get your weapons back when you throw them. Being able to spam Magic Stone might help here.

In terms of funny: whatever is lying around, finishing up with the sink.