AdminActivity

Features:

Records online time for any player
Configurable reset timer
AdminSigns that can show the top 3 staff members' online times
Sign updating in real-time
Works with skulls to show the top 3 player heads (picture below)
Fully-customizable plugin messages
AFK detection w/configurable AFK time

This is an example of the Top Staff signs

If you want to use the player heads on your display, make sure the config option UseSkulls is set to true. It should default to true but it's always best to check.

Make sure you have the aa.sign permission before placing signs. Otherwise, you will not be able to create them.
Place any skull down in the orientation you want the head to face. The skull must be one block above and one block either north, south, east, or west.
Place down a sign. On the first line of the sign, type [AA] followed by a 1, 2 or 3 depending on which position you are making a sign for.
Ok, you are almost done. Make sure you click done, not escape. Clicking escape will not update the sign properly.
You're done. If you followed the instructions, the player head have changed and the time of the 1,2, or 3 staff member will be shown on the sign.

You're Done!