Unsee - The ability to open a chat session and message then delete it from history forever just like tlk.
Waver - Description: Google Wave is a great way to communicate and collaborate. Waver lets you:
Chatango - Add free live chat to any web page. Chatango is a live group on your site
Rizzoma - Email and IM are linear contextless communication tools.
Walkaround - Walkaround is a variant of Wave, based on the Apache Wave code base, that runs on App Engine.
Microsoft Teams - Microsoft Teams provides the enterprise-level security, compliance and management features you expect from Office 365, including broad support for compliance standards, and eDiscovery and legal hold for channels, chats, and files.