I've heard of a guy who kept clones in the fridge for up to 2--3 weeks.
But after that his sucess rate for them went way down.
Storage isn't a good term. Clones are alive. You can retard their growth for awhile.
There is a method used to keep them in stasis for a few weeks, by keeping them in the crisper of the fridge, stems submerged in water. But as stated, the survival/rooting rate decreases pretty severly.