Is there any way of telling
1. Who is currently logged in
2. Who has logged in recently, or in a given time period etc.
3. Reporting a history of log ins
Mattias Lövström from ElektroPost made an example of an plugin that uses the logservice to display recent user activity. This was part of the recent tech forum in Stockholm in November. The code is available as a zip file here:
http://www.episerver.se/pages/29846/Code_UserView.zip