While Wi-Fi can only accurately determine your position indoors to within about five to 10 meters, Ryan and Ganick say, ByteLight's technology cuts this down to less than a meter—close enough for you to easily figure out which shirt the deal is referring to.

ByteLight is working on a functioning prototype, and hopes to have the first products available within a year. Ryan and Ganick say a number of developers are working on smart-phone apps that would include the technology, which, they feel, could also work as an additional (or smarter) location-finding feature within existing apps.

The company is talking to retailers about installing its equipment in stores, too. Ryan and Ganick think businesses will warm to ByteLight because installation mainly requires buying and screwing in their lightbulbs. Once a business installs the lights, they'll need to use a ByteLight mobile app to determine which light corresponds to which spot in their building, Ganick says. An app developer could then use that data to tag deals to different lights.

And while LED bulbs are more costly than standard lightbulbs, they've been falling in price. ByteLight says its bulbs will be only "marginally" more expensive than existing LEDs.

Jeffrey Grau, an analyst with digital marketing company eMarketer, believes ByteLight may be on to something. If the customers are already inside a store, showing them an exclusive offer makes it more likely they'll buy something.

But will shoppers find ByteLight's targeting creepy? Ryan and Ganick don't think so. They say an app on your smart phone would be "listening" for nearby ByteLights, not the other way around. So users can control their own experience. And the LED bulbs' positioning capabilities could help people inside a large building solve the common problem of figuring out where they are. "We want people to think about lightbulbs in an entirely new way," Ganick says.