Love to show up to order a food and see "$1.75" change to "$2.95" as my finger hovers over the "buy" button.
I think they need to take this to the next level and make every purchase order one of those penny-auctions, where you pay $.25 to bid on something that starts at $0.01 and has an army of bot-straw-purchasers bidding up the price every time you place an order.