If you could buy a product at the lowest possible cost, assuming everyone creating the product was fairly compensated, you'd take the lowest possible cost.

Regardless if consumers sought information about a product from a Google search or a Yelp or Amazon review, all else being equal, if they could buy at the lowest cost they would. 

Hence, in this world of increasingly perfect information, or at least more information, how does a retailer compete on price against a comparable brand? 

One way is to have as much intelligence on a competitor's pricing. If Walmart knew that its $149 price for a Fisher-Price - Starlight Papasan Cradle Swing was selling for more than than Toys R Us' Fisher-Price Startlight Cradle 'n Swing - Sugar Plum, which was selling for $135, then Walmart may lower its prices. 

This ability to know real-time pricing has been pretty hard to come by, until today, as new companies emerge to make this data available. 

Upstream Commerce announced Tuesday morning that it's raised $3 million in financing from YL Ventures, Bright Capital, and new private investors, to make pricing more transparent. 

The new funds will help the Tel Aviv and Boston-based startup, which has raised a total of $4.5 million in funding since its founding in 2009, to establish more strategic partnerships with companies that can help it tap into retailers so they can compete more effectively in a world where consumers are much smarter about pricing. Currently, Upstream works with such customers as Toys R Us and Staples.  

The prices are all publicly available, but Upstream Commerce crawls the Web, said Gilon Miller, head of marketing at Upstream. Upstream uses technology to gather that information and update prices every 24 hours.

Heretofore, retailers would get the information quarterly, leaving them little ability to respond quickly when prices are lowered by a competitor.  

Upstream Commerce is looking to change that.