We've got some new toys to play with on the cart. We've got an iPad to use as a cash register, and a rubber stamp for printing our logo on the boxes.
Just an ink pad and a rubber stamp, branding made simple...and cheap.
You can learn more about the Square Register app at Squareup.com. Basically it lets us process cards using the little card reader that attaches to the headphone jack. The iPad acts as a point of sale system, allowing us to create custom buttons for ringing up sales. It then tracks our inventory usage and gives us some pretty nifty sales analytics.
BTW using square we also accept "Pay by Square" as a payment method.