I just thought of an example.

(Priority 1-3) are champagne glasses stacked on top of each other. (P-3) is
on the bottom, (P-2) is in the middle and (P-1) is on top.
The champagne bottle is the "savings"; when the "savings" gets distributed
into the three savings accounts (Priority 1-3) it gets poured into (P-1)
first, then as (P-1) receives its budgeted amount, the savings continues to
proceeds to (P-2), and so on.
When the three prioritys are filled the remaining savings stay in the
original savings account.

rvaughnp