Another great idea from Google

Google has filed for a patent for a digital billboard system that’s brilliant. Displays inside local malls would be connected to a new Google ad engine. Retailers would create and schedule ads for actual products in their stores that would run on nearby displays with Adwords-like targeting. When the product in question is sold out, the retailer’s inventory system would automatically notify Google, and the ad would disappear from the displays. Pretty cool, eh?