Imagine walking by your favorite store and instantaneously receiving a message on your cell phone letting you know that the store is having a 25 percent off sale, for one day only.
That scenario isn't too far away.
In February, Placecast, a San Francisco mobile advertising company, launched a location-based advertising program called ShopAlerts, which gives customers geo-triggered messages.
Placecast draws a virtual "geo-fence" around a certain location, and when a customer steps into the fenced area, he or she receives a location-specific ad.
"Geo-fence technology represents the next frontier for digital marketing as consumers expect to connect with brands at the right place and time, all via their mobile device," Alistair Goodman, CEO for 1020 Placecast, said in a statement when ShopAlerts launched.
Of course, not all consumers may want to sacrifice that personal piece of real estate they might lose with location-targeted ads. But Placecast's program only applies to customers who opt-in to the program, with brands and promotions that they choose.
Maybe you don't want an ad sent straight to your phone, but how about instant mobile messages about places you could find your favorite music or favorite foods?
That's what Loopt, one of the first geo-social networks, provides its users. Once users check in, they can access a stream of information about where they are, from local points of interest to location-specific tips from other users.
Sam Altman, the company's co-founder and CEO, said this week at a panel that a person's location history is a powerful identifier.
"It's an amazing and rich data set for targeting people," he said. "You really are so a product of the places you've been, even more perhaps than the Web sites [you've visited]."
With the location history as a guide, he said a service could learn a person's tastes and patterns and then recommend tailored information.
In a recent piece for the Wall Street Journal, Altman said that future services could learn the time and route of a person's commute to work and send alerts when there are traffic delays on that route. Another service could recommend restaurants enjoyed by people who have also liked the same restaurants.
Privacy is certainly an issue, but Loopt has said that it gives users control over what information is shared and how it is used.
Google's Lee said that an especially interesting application of location-based technology is the ability to document or share a rich, multimedia account of a significant experience.
With Google Latitude's location history feature, users can keep a record of their past locations and then review them on Google Maps or Earth.
He said the feature could be valuable to people wanting to recall a special vacation or trip.
In a few minutes, he said, a user could review the locations stored by Google Latitude, make edits if necessary, and then marry that history with photos taken along the way.
"Because photos have a time associated with them, you can then correlate that to your location history and it automatically geo-codes," he said. "In a very short amount of time, they can pull together a nice package detailing their trip to share with family and friends."
And what would location be without maps?