Are there any real-time indicators of site traffic available? I'm aware of Real time SE specific traffic page?, and my question is different.
I'm thinking more along the lines of access to real-time data such as number of people currently viewing something/anything on the site, number of users currently logged into the site, or number of site pages currently being viewed; basically raw data that is likely collected automatically and doesn't require much processing resources for summarizing, aggregating, or filtering. This could be one or more such indicators that could either be displayed routinely as a count and identifying label, or some form of query that could be run. Or might there be a user script that does this?