NoVirusThanks Shutdown Logger is a service-only app that logs the date, time, and uptime of logged in users.
This can be extremely useful for keeping track of who has been on your machine while away from home (like your kids) or if you leave your desk at work. It takes up almost runs in the silently in the background logging every PC shutdown, who logged on and the duration spent. The details are saved to a simple text file by date.
For space saving, NoVirusThanks Shutdown Logger will auto-delete any log files that are greater than 30 days old.