Keybase Chat - End-to-end encrypted chat built into Keybase
Seald - Keep your conversations secure, everywhere.
Xifrem Chat - Client-side encrypted chat with asymmetric encryption
Hermes - Pandora Client for OS X
Brie.fi/ng - Start secure group video chat
Cyph - Cyph is the name of a completely free chatting website that provides its visitors with a secure and safe chatting environment.