Camelcamelcamel - Easily monitor Amazon product prices and get alerts when they drop.
Paribus - Find out for free if online stores owe you a refund!
GlassIt.co - Find discounts, without invasion of your privacy. Download Glass It Price Tracker mobile app or browser extension 🇺🇸
Lolli - Earn bitcoin when you shop online
Pricy - Amazon price watch
Slice Watch - Get an email when an item you've added drops in price 💸