I've just been considering that I found would find it very useful to be able to view certain details about the number and types of users online at any time. In particular, the following statistics I would find quite helpful for the given reasons:
- Number of users online - generally useful to determine how people could potentially answer your question, or whether you might find a question you can ask.
- Breakdown of number of users online by a) reputation, b) favourite tags, c) number of questions asked, d) number of answers made. All these could possibly be used in a user's judgement of whether it's worth them idling around StackOverflow at the current time.
- Current/recent traffic rate (page hits per second?) - gives you similar info to point 1, except it largely ignores "inactive" users that are online.
- List of moderators online - perhaps most useful for other moderators so that they know when someone is watching the questions.
- List of 'famous' users online - mainly for curiosity/fun.
What are people's thoughts on these ideas? Has it been considered previously? Certainly I see no technological obstacle to implementing such a feature.