Mailspring - Mailspring is a mail client for Mac, Windows and Linux.

Camelcamelcamel - Easily monitor Amazon product prices and get alerts when they drop.

Thunderbird - Thunderbird is a free email application that's easy to set up and customize - and it's loaded with great features!

Fetchee - Fetchee is a free price tracking wish list app that works with all online stores worldwide.

The Bat - The Bat! is a secure desktop email client for Windows, designed to protect your correspondence against third-parties and to save your time.

Keepa - Price history charts and the option to be alerted on price drops for all Amazon sites.