Messenger for Mac - Facebook Messenger wrapped up as a desktop app
Goofy - A Mac app for Facebook Messenger
Chatterino - Chatterino is a chat client for twitch chat.
Caprine - Elegant Facebook Messenger desktop app
Chatty - Chat with strangers all around the world in Messenger
Picatic - Picatic encourages event organizers to create a custom website, sell tickets and then determined their cost of use. Selling out events is easy with Picatic.