AmabayFox is a Firefox extension that allows you to use amabay.linked8.com to compare prices between Amazon and eBay for any product at one click.
How AmabayFox Works
Under current version (1.0), after install, AmabayFox unobtrusively inserts a button on Amazon product detail and browsing pages, clicking on it sends the product ID information to our server, and our server responds with Amazon and eBay product prices side by side in a new Firefox tab.