Camelcamelcamel - Easily monitor Amazon product prices and get alerts when they drop.
TrackIf - Alerts you if the price of your favorite products drop
Fetchee - Fetchee is a free price tracking wish list app that works with all online stores worldwide.
Coupofy - Coupofy is USAs number 1 trustworthy deals and coupons website.
Savelist - Found products you want but not ready to buy?
LoveSales - Find and save products you love, get alerted when they go on sale.