190 reviews
  • Nice little shopping gadget...I like the way it only pops up when your seriously shopping - the rest of the time it's hidden away. Always manages to save me a few quid. Definitely a lazy person’s way of making sure you're getting a good deal without having to trawl around the web - especially if you're speed-shopping like I tend to do!
  • I like the fact that it only activates when it realises i'm shoppping and apart from that there is just a green arrow in the corner of my screen. It doesn't seem to work on every site but when it is functioning, and you are shopping, it is very useful indeed. I was hoping a tool like this would come along. It really takes the drudgery out of looking for a deal online. Great for saving time and money :)
  • The add-on is polluting.

    Error: Components is not defined
    Source file: chrome://canitbecheaper/content/invisiblehand.js
    Line: 48
    aSubject = aSubject.QueryInterface(Components.interfaces.nsIHttpChannel);

    Components is not always available.
    It is however always available for aTopic is http-on-examine-response and http-on-modify-request
    So, make sure to check for those two first before trying to access Components
  • It is the best addon I have installed in three years of having firefox. I saved me £100 on a TV and usually £5 whenever I buy a game online
  • Not entirely convinced with this, seems to only work with Amazon and when I search on one product then change to another it no longer searches. I have to come out of the browser then search again. As per another review if this is not a problem for you then this is a good plugin, however I wont bother with it as it seems to be limited to one web site (Amazon) that it does it comparison searches which to me is not a great idea; I would want it to be able to do this on all the big online stores Play.com, 24/7 Electrical, Empire direct etc etc etc.
  • Generally seems to work fine, however...

    I mostly use play.com and amazon.co.uk (often the best prices/section). It seems that it will compare Play prices to Amazon prices, but not vice versa. I prefer to browse on Amazon, so this means I have to manually check Play prices each time, which kinda defies the point.

    Also, I would rather it allowed you to switch off automatic checking and let you just check using the status bar button on demand. I find the automatic checking of each page unnecessary most of the time, and that it slightly slows down browsing.

    If the above are not problems for you then this seems like a good tool, and it definitely a good idea. Unfortunately, the way it functions at the moment it isn't for me.
  • When I installed the plugin it wanted to update and hung up. I dont think it was the plug though as much as my old computer. Works great now.
  • Is play.com supported as it is shown in the screenshot? But doesn't come up in list of retailers.

    Very good add on and very useful.
  • Does the list of retailers include tech sites such as NewEgg, ZipZoomFly, PriceWatch, etc.?
  • I think you should add support to Canadian stores/sites.

    But anyway it's really seful for those who live in the US or UK
  • Sounds extremely useful, but it needs support for more countries. I'm in Denmark, so this is not really useful for me - yet. But it is a truly great idea.
  • Many thanks for this money saving add-on. Works very well for me and have already saved a few quid. Excellent...

  • Surprised that there is no option. It doesn't work for me. Maybe it is because I am in Canada but in the case that I am on the US site, it again doesn't show anything. However it could be extremely useful.
  • Waiting for Canada Support!
  • Sit's in the background until you need it. Saves you money. It's a no brainer download!
  • Fantastic add-on, works in the background and is completely unobtrusive. You forget it's there until you buy something on-line. It saved me £51 on a Sony E-reader!
  • I'm all up for using anything that can save me a few quid and it quotes up to the minute prices. Love it!
  • Fantastic add-on, works in the background and is completely unobtrusive. You forget it's there until you buy something on-line. It saved me £51 on a Sony E-reader!
  • it really doesnt work for me. slows browsr down to a CRAWL and there is not real coverage so most of the time so no real offers and oftentimes the difference or saving is about 2c. Which sucks. also it doesn't consider shipping or any other information.
  • Works well with popular items, but not so well with unpopular items.

    I use it (unashamedly) with our extension to save even more money: cashbackautomator.com.
  • Working perfectly for me on tons of sites! Saved me over £13 on a PS3 game and over £20 on a DVD boxset, without all that comparison legwork.
    Discreet too, nice!
  • I really wanted this to work but it just does not. It is always gray no matter which site I am on and I am on Amazon all the time looking at very popular items like games, books and simple kitchen items. This has not once shown me a price option. Also I cannot get into the add-on options for this add-on, is it possible? I will leave it just in case it starts to work like I said I really would like it to work. Thanks.
  • The worst thing about this extension is that when it runs, it locks up Firefox completely, and it can take quite a while to run. Second, its selection of retailers ("over 50") is quite small; this is no substitute for a search engine. Third, it doesn't count shipping charges, which throws off its comparisons, making many of them inaccurate.
  • Awesome extension, absolutely necessary when buying textbooks. It would be nice if in the future InvisibleHand compared prices for new and used (eg. on Amazon) products and account for shipping prices.
  • Excellent! It keeps saving me money

    Every time I shop for something, it either finds another store which sells it for less, or it reassures me that I've already got the lowest price. It reminds me a little of that Arthur C Clarke quote about how any sufficiently new technology is "indistinguishable from magic"

    I guess it's not actual magic, but it's very very clever. I'll definitely be keeping it.