Real Cost is a chrome extension that replaces dollar prices with equivalent costs where the units are real goods. In particular, costs are replaced with the number of meals you could provide at a food bank with the money.
This extension currently only works on certain websites. New websites are being added from time to time (feel free to submit new code...)
This extension is currently not in the chrome web store. To install it, you need to download the .crx file above, and drag and drop into chrome.
Once it is installed, you need to click on the '??' icon in order to see it in action.