https://crypto.cat

Cryptocat is an open source web application intended to allow secure, encrypted online chatting.[1][2] Cryptocat encrypts chats on the client side, only trusting the server with data that is already encrypted. Cryptocat is delivered as a browser extension and offers plugins for Google Chrome[3], Mozilla Firefox and Apple Safari.

Cryptocat intends to provide means for impromptu, encrypted communications that offer more privacy than services such as Google Talk, while maintaining a higher level of accessibility than other high-level encryption platforms,[4][5] and furthermore allows for multiple users in one chat room.[6]

Möglich wird das durch eine clientseitige AES-256 Verschlüsselung, der Diffie-Hellman-Schlüsselaustausch Methode und Whirlpool Verifikation.

You not anonym with this tool ! "They" know your ip, for this point it is important to use a VPN + Proxy + SSH

Pidgin works with tor and has OTR. That's what most people use anyways.