The $1 coin is a great idea - but it cannot succeed in isolation. We need to do three things together:  get rid of the penny, put the $1 coin into wide circulation, and bring back the (long-neglected) $2 Jefferson note. This solution solves the problem of what to do with cash registers. The slot for the pennies is replaced with dollar coins.  And the place for Washington dollars is replaced with $2 bills.  When getting change for a $10 bill, wouldn't you prefer four $2 notes and a couple of coins?