Under what circumstances do items count against your hand limit? It's my understanding that a big rock or something counts against your hand limit until you throw it, at which point it's available to be picked up by anyone. But how does that jive with things like tacks which are meant to be dropped on the ground immediately - are you still maintaining the spell even when the item is just laying there?
But then once someone picks it up, does it count as being maintained by them?
Also, under what circumstances can you dispel an item spell? Only if you're holding the item? Only if you're the original caster?