Picture 3Here’s an interesting little beta that could have a lot of viral traction.

Postabon is a location-based service that lets people tag and share deals they find while out shopping. It marries two concepts that have caught the attention of venture capital firms in the last year: marking-up the places around you through mobile apps and using the power of crowds to drive sales.

Users upload and vote on the best in-store discounts. They load the Postabon iPhone app or go to the web site and enter info on the deal. It gets automatically geo-tagged and uploaded to the service. Postabon incorporates some gaming elements into its app — you literally get Karma points for sharing deals and compete on a leaderboard with other users in different categories and regions. Other Postabon users can follow your profile for deals, if you’re especially good at ferreting out shoe sales, for example.

Since launching a pilot last week, the site has brought in 600 recommendations, covering sample sales and happy hours mainly in Manhattan. Conceptually it seems like a promising idea — it taps into natural behaviors like sharing and letting friends know about a good deal, while offering value every time you log-in, because you never know if the place around the corner is going to start offering free coffee or massages.

Postabon is being bootstrapped by its co-founders, John Buchanan and Stuart Wall, who both just finished Harvard Business School.

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