The jilted prom queen's comments aside, one option you might want to consider is one or two Craftsman single-drawer intermediate "boxes" that they sell, that go between a top and bottom box. You could hang one of those under the bench top, and it wouldn't break the bank.
I've got a 3-drawer, ball-bearing intermediate box made by Clarke that I put on a cart I built--very handy.
A couple of guys here bought Harbor Freight full-size bottom boxes, and put those under their bench--decent price, and very practical.
-Brad