Yes, and it has been running for several years now. Very handy.
In Japan, the customer doesn't have to mess with any lockers. In the convenience store (Lawson instead of 7 Eleven) there's an electronic terminal used for buying tickets, pre-paid cards, etc. The customer inputs the order code and key into that terminal to print a ticket. Then they hand it to the clerk who picks up the package from the storage.
Amazon Help Article (JP): http://www.amazon.co.jp/gp/help/customer/display.html?nodeId...
Google Translate: http://translate.google.com/translate?sl=ja&tl=en&js...