What about traces? You can set up a trace to log your logins specifying NTuserName and LoginName and also a DatabaseName or DatabaseID field in the Data Columns for the events Audit Login and Audit Logut or Audit Login Failed. It could be done by running a script, so it would run without Profiler being open on the workstation or server.

Another idea: why don't you setup 1 database server licensed per processor with good hardware for several application servers if only a few users use each application? You may keep all of your internal databases on 1 server and may keep your current application setup with several applications on each application server

Yelena