At first this spell looks like a total waste of time, since all it does is to seemingly destroy one object in the caster's possession. However, nothing could be more wrong. Casting it on a selected, not too-complex item (namely nothing plot relevant) causes it to only vanish into the void, where it is safely stored. This way, the mage can carry around heavy objects without being concerned about the weight.
To get the object back, the Reappear spell has to be cast.