Until nixon axed the large bills as part of the drug war. With 1000$ being the new largest bill, gold bars/coins became a potentialy practical option once again. Krugerrands (sp?) tried to capture this market but never caught on.
Considering inflation a $100 note today is comparable to a $10 note from just a few decades ago. Thus currency denomination should shift in the opposite direction eliminating the cent and nickel, and adding larger notes.