I'm looking for a strongly visual but still simple alternative to text-based chat. The important feature I'm looking for is a friendly visual representation of user state/emotion (available/away/busy), with a rough analog to actually being a room together. Chat would still be text-based, persistent (doesn't fade away) and mostly public (directed to the whole room). Visually distinguishing directed public chat would be nice. Private chat must also be possible. Being able to move avatars to different areas of the room would be nice.
Simply having large customisable avatars on the side of a chatroom would be a good start. Does anything like this already exist?
Ideally this would be an open standard technology built on existing standards (XMPP?), with no need for a server or a very light server, with an open-source, cross-platform client. And a pony.
For non-web-app answers, see see http://superuser.com/questions/217129/simple-visual-virtual-presence-chat-client
Example of a mythical good answer: A one-screen Metaplace room with persistent chat history. (Pity Metaplace no longer exists and didn't have a persistent log.)
Example of a poor answer: Microsoft Comic Chat: very visual but poor/confusing chatroom history, also no longer supported
Example of a bad answer: Second Life: big download to install, lots of bandwidth to run, complicated virtual environment, complicated user interface