Site Palette - Get the essential colours from any website
Rainglow Color Themes - 320+ color themes for a variety of editors and software.
Color Palette Generator - Enter the URL of an image and find its color palette
Slack Themes - Make your Slack pretty with custom themes
Palette For Mac - A menu bar based colour contrast analyser
eM Client - eM Client is a fully-featured email client for Windows and macOS with a clean and easy-to-use interface. eM Client also offers features for calendars, tasks, contacts, notes, and chat.