It is a DVD vending kiosk generally found at Walmart or McDonalds.
$1/day. You can see what videos are at any particular location online, reserve the ones you want and go pick them up. You can return them to any other redbox kiosk in the nation.
We were on vacation and we rented a movie in the town we were vacationing in and the kids watched it on the trip home and we returned it to the one closest to our home.
http://www.redbox.com