Hey Vik, I'm sure you have this script (or some variant), but this tells you who (or what) is active on the system.
It's not the same as who's left their workstations on because the SIMS application creates an SQL connection on demand, then deletes that connection so it can never be 100% accurate, but it's something.
It works on multi-hosted servers, too, provided your database names start with 'sims'. Change as needed.
You can schedule it to make a 'naughty list' of who to blame when your upgrades go wrong. :D
Code:
use master;
select sysprocesses.loginame as [Logged-in user], sysprocesses.hostname as [Machine name], sysdatabases.name as [Database name] from sysprocesses
join sysdatabases on sysprocesses.dbid = sysdatabases.dbid where sysdatabases.name like 'sims%' order by sysdatabases.name