Lists items cross-reference possibility

[Dizzy77]

Is it possible to make one list reference (and show) items form other list? If so can lists from different sites on SP also make this?

My problem:
I have a list named ListA in top level site and list named ListSub in subsite named SubsiteS.
Assume that both lists have same columns.
Is it possible to make subsite list ListSub to show some subset of items from top level site list ListA? In other words can a subsite list show(reference) items from top level site list without copying them to it self?

Normally in this situation ListSub is only a specific view of ListA, but I need ListSub to have items that are not in ListA.
So can a list somehow reference items from other list by some specific key or filter and show all of them?
Best solution I have for now is to create copy of items I want from ListA in Sublist. This is made attaching a ItemAdded event handler on ListA and copying this added item to Sublist if some criteria is met?

Thanks
Daniel