When I asked the company to suggest a search that would best demonstrate Slifter's value, I was told to search for a Canon D40. Sure enough, the first listing accurately showed many nearby stores selling this common model, complete with distances from my location. While any yellow-pages search could have given me the same list of big-box electronics stores, there was indeed a glimmer of hope. I could see from my Slifter search that all of the stores were selling the Canon D40 for the same price: $599. This search return could, in theory, spare me from wasting time hunting for discounts.

Slifter currently has 200,000 members, most of them using the free application (which allows searches only by zip code); a $1.99 monthly subscription allows the more-precise GPS-based searches. Companies also pay Slifter a small fee each time a user opens a search result.

Paul Rademacher, a software engineer whose credits include superimposing Craigslist real-estate listings on Google Maps, says that Slifter's interface needs work. "The problem is that the results are not organized ... and there's almost no information provided with the link."

Muller argues that Slifter could get better if more retailers furnished information. "Here's the way we view it," he says. "In 2007, most retailers, irrespective of size, are managing inventory electronically with programs like Quicken Point of Sale. These can let you export your inventory." Slifter updates its database daily.

Jeremy Kreitler, director of product management for Yahoo Maps, says the big players in search aren't yet attempting Slifter-like services because of the lack of "great, comprehensive, clean data" on inventories. Outside of consumer electronics, inventory data often isn't available, or the quality is "questionable" at best, Kreitler says. That's the main stumbling block; creating better search tools is relatively easy, he notes.