You can see that info easily in the FMS admin console. Do you need it IN your solution?
One way of doing that would be to use a server-side script sequence schedule and use the "fmsadmin" command line on the server to output the data to a text file, move it to the FMS documents folder and have a FM script import it.
That would make it always accurate, as opposed to a login system that may show false positives if user's machine get disconnected without logging out.
Very clever, Wim.
That really is a clever solution - my bruteforce idea of building a login to capture connected users in some table had the obvious faults of not handling disconnects which was my first major objection, when I thought of it. But I couldn't come up with a different idea so this may have saved the bacon!