Price searching and comparing engines are currently all the rage. This fast-growing segment got its wings thanks to the unfortunate economical climate, when every dollar counts. One of the companies that are trying to push themselves is Forward Internet Group, makers of the Invisible Hand Firefox plug-in.
This Firefox plug-in features price comparison between 30+ e-tailers in US and 25+ in the UK, which are the two main markets InvisibleHand is focusing on. The plug-in includes sites such as Amazon, Best Buy, Newegg, The Home Depot, Wal-Mart in the US or Argos, Dabs, Dixons, HMV and so on.
Currently, Invisible Hand is in beta, so we were a bit cautious when it comes to surfing experience. We installed the plug-in, chose random five items [netbook, Blu-ray movie, PC game, cellphone and an LCD monitor] and visited couple of different e-tailers in the US and UK.

Invisible Hand shows percentage and actual money saved, alongside with the lowest price among e-tailers
Invisible Hand waits until you’re on the product page on one of their supported e-tailers, and then does a background search, and rolls down showing if the site you’re on has the best price or not. In all of our five searches on sites in US/UK, Invisible Hand came out either with "This is the best price (xxx.xx) out of x offers!", or "Save X%! This item costs X.XX less (XX.XX) on Etailer" sometimes finding the better price elsewhere, sometimes informing us that we’ve found the best price.

Invisible hand can even check a hidden price on sites with such policy, such as Amazon or Newegg
The neat feature was that the plug-in works even when Amazon hides the price ["Click to see price"], for instance. Our evaluation didn’t pass with flying colors, though. Given that this application is in beta, we can forgive that sometimes price simply doesn’t come up – it can happen if a product name too confusing? for instance, we had a very hard time finding price comparison on LCD display such as ones from Samsung, LG and others.
All in all, this price comparing plug-in has some serious potential.