I just noticed that Allrecipes.com has a new feature that allows you to see what ingredients are on sale in local stores. Any idea where they are getting this information from?
After taking a look at the source code of the widget on a sample recipe page (selected at random by me), it appears that they are using http://corp.groceryserver.com/ as a data provider
For example, the recipe at http://allrecipes.com/Recipe/Sherry-Braised-Beef-Short-Ribs/Detail.aspx makes an AJAX request to http://allrecipes.groceryserver.com/groceryserver/service/w5fDoHvC... which returns JSON about the sales. Note: I tried to base64 decode that string and some variations but didn't get very far.