Just how do I figure out that is logged right into Windows XP?
qwinsta from the command line need to show you that browsed through, though I'm not exactly sure if that's simply for incurable web server sessions or otherwise.
C:\Users\wumpus-home>qwinsta SESSIONNAME USERNAME ID STATE TYPE DEVICE services 0 Disc >console Jeff 1 Active
psloggedon - a tiny energy that becomes part of the SysInternals Suite of devices
Stand - alone link : http://technet.microsoft.com/en-us/sysinternals/bb897545.aspx