Depends on the parts. If I am stripping down a bike for scrap the usable parts go in a stacking bin for spares for whatever/whenever. Bikes that are getting stripped down for an overhaul the parts go in a box/bin to be worked over as needed. If I am doing and upgrade or build parts go in a bin for that specific bike. Otherwise they are more or less in a pile by type. I started a bike inventory list a while back it kind of fell by the wayside. I guess I am not OCD enough, as in not at all.
Aaron