Interesting idea, launch it and choose Mac/iPhone/iPad to see a list of apps that have been discounted, which you can then filter by free or paid, as well as narrowing down the category of app.

Clean straightforward interface (while there's no Preferences option to customize it, there is a button to send the app to the menu bar). The main problem I had is that clicking on an app in the list caused a window to pop up for a second saying 'loading app, please wait' but then... nothing. From the description it says it takes you to the app page in iTunes or the Mac App Store. Unfortunately in my case it does neither, even if I load iTunes or MAS ready for it to do its thing, it steadfastly refuses to show me the app so it looks like there's one or two little bugs for them to sort out? (Am running this under Lion 10.7.2).