Your avatar can move around the room and talk to its occupants. There are usually additional rooms to explore. You can try The Palace , one of these communities, for free. Suler has also researched the interactions in communities such as this. His paper on Life at the Palace summarizes examples of his naturalistic research.
Some online counselors use chat rooms extensively to interact with clients.
This interaction is much more immediate than email, but also somewhat less convenient. On the fourth Tuesday of every month we have an open discussion of mental health issues for the general public. Psychologist John Grohol hosts similar chat sessions three days every week. They are an opportunity for anyone to interact with a psychologist. The sentences are less staccato than in some chat sessions, and the subject is always some aspect of mental health.