Autowork

Chutes with filter

The cobblestone goes to left barrel, everything else to right barrel

Useless machine

Minecart Loader

Minecart loader places minecart with chest (from storage above it) and fills it with items from storage behind the loader

Minecart Unloader

Minecart unloader removes the minecart with chest, puts it in the storage above the unloader and puts its contents to the storage behind it (in this case, into Placer block)